There’s always something to howl about

Debunking . . . got itself a ton of new venture capital yesterday, so today seems like a fine time to deconstruct its praxis.

When Zillow was brand new, Catherine Reagor, the dippy local real estate reporter for the Arizona Republic wrote:

Want a reality check? Go to, a new Web site with a program that calculates a home’s value for free. It values several Valley homes for tens of thousands less than the price listed on them.

At the time, I said this in response:

If you want to know what your house is worth, do not go to, which delivers completely useless estimates of value for free. Even Net Value Central, a tool used by professionals, lags the market by a month or more. The only way to price a house is to work as rigorously as possible from current and recently-sold listings for extremely similar properties. If you price your house to sell from sources like, you will give thousands of dollars away. If you rely on to tell you how much to offer on a home, you will see it sold to someone else.

(You can prove all this to your own satisfaction, if you like. Most of Ms. Reagor’s mistakes seem to come from falling in love with ideas she doesn’t check out. Here she tells us that she ran on live listings and found it came in much lower than the listed prices. How did it do against sold listings? She didn’t check, but you can. Run on the sold homes documented in your local section of the Republic. You’ll see that, time after time, is substantially under real-life market results. It’s a useless toy, which Ms. Reagor might have discovered on her own had she bothered to test it properly.)

Just lately, I needled the Zillowites a little more:

All right, here’s the deal with

I decide I’m going to buy you a pair of designer jeans, nothing but the best for you. I know that fit is important, so I go to three of your best friends to get their sizes. Not yours, theirs. I strike a happy medium amidst the diversity, reckoning that — what the heck! — you can’t be that different from your friends.

If the jeans I buy for you actually happen to fit, this will be a happy accident. More likely, the jeans will be a close but not perfect fit.

You understand why, of course. Epistemological error was built into my sizing algorithm. I chose a method that might have been convenient, but which cannot possibly produce objectively accurate results with any degree of confidence. Arguably, the more of your friends I measure, the smaller my margin of error. But I am still pursuing an inherently erroneous sizing methodology.

For Realtors, a perusal of the tax records, the equivalent of a Zillow Zestimate, is the first step in comping, the step known to be least accurate. The next step is comping the house one-for-one with recent past sales and currently-marketed (competitive) listings. The last step is working all those numbers against the subject property in its current state of upkeep and upgrades.

In the same way, if I don’t take a tape rule to your inseam, the chances of my getting jeans that fit your unique physique are very poor.

A very nice flak-catcher — everyone at seems to be very nice, and they are all over the Cluetrain idea — had this to say in reply:

I obviously can’t share any secret math but can let you know that you’ve only got one part of the process captured in this story – for example, you forgot to mention that you also took last pair of jeans I bought from my closet and recorded its size – and you did the same with all my friends who bought jeans around the same time . . . etc.

That’s cute, but it’s not responsive. The main charge stands: cannot do what it promises and purports to do, because it is simply not possible to price a home you have not seen. That the algorithm they’re using might be better than I envision it to be means nothing. That it might be successively revised through time to become even better means nothing. The entire methodology is based on a fundamental — and painfully obvious — epistemological error, and if particular results happen to be more or less consonant with objective truth, nevertheless, cannot ever achieve — nor even approach — objective truth.

Want proof? Let’s look at some houses.

These houses are all from an historic neighborhood in Central Phoenix called the F.Q. Story Historic District. This is the first true suburb of Phoenix, the first organized, subdivided stretching out from the original square mile of Downtown Phoenix. Story was a commuter suburb: Residents rode their horses to town, or took wagons, automobiles or streetcars. The homes were built mainly in the 1920s and 1930s, and they were all one-off, custom construction. Further north, you can see the beginnings of the techniques that became production, tract-home building, but in Story the homes were all built like custom-tailored gowns, each builder expressing his own ideas of what a home should look like. In consequence, these homes are highly prized and sell at a huge price premium over later-built tract-homes with comparable space and amenities.

To be fair to sellers and other Realtors, I’m citing either homes we listed or which are not currently for sale.

1102 West Culver Street

We sold this house in February of this year for $480,000. Zillow has it at $493,712, a reflection of the process my correspondent was talking about. If fact, this Zestimate is probably too high, given that nothing is selling in the neighborhood right now. Don’t worry, though. This is as close as we’re going to get to reality.

922 West Culver Street

We have this house under contract right now. The list price is $495,000. Our price is based on a complete appraisal. Zestimate: $297,319 — only off by $200,000. Realtors on the ground can see the value that computers can’t. You can barely see the house for all the trees, but that is a huge bonus in scorching Phoenix. The house also has a huge sun room, which we excluded from the appraisal but which sells the house to everyone who sees it. It’s the ultimate family space, a vast retreat for playing foosball or watching TV. (Addendum: This house sold for $475,000 on 10/12/06.)

1110 West Culver Street

We have this home listed for $450,000, again backed up with an appraisal. This is two doors west of 1102 West Culver Street, but evidently the Zillow algorithm doesn’t lift all boats with a rising tide. This home is also larger, eight years older and has a second bathroom, all of which are worth money. On the down side, it lacks a pool and doesn’t have elaborate desert landscaping. We are very confident the price is reasonable. (Addendum: We reduced the price to $424,900 after I wrote this.) The Zestimate: $311,648.

1142 West Willetta Street

This home is listed at $519,000. It’s a breath-taking restoration of a 1935 Moroccan Revival home with a sybaritic master suite and a spacious guest house. Zestimate: $377,483.

Now, to this point, you could say that this is all so much sour grapes. doesn’t like our listings. Boo hoo! I invite you to pay close attention to the next house, which is not currently for sale:

925 West Willetta Street

The brown stuff you see where the roof should be is planking. The gray stuff showing through the planking is sky. The roof has been off of this house for a long time. Until this spring, there was a tarp over the planking in back. That failed in a storm, and I can’t imagine how much water was dumped into the house. It rained hard last night, too, so, whatever the home was worth yesterday, it’s worth less today. But don’t think for a minute that it’s worthless: It’s Zestimated value is $337,725, more than 922 and 1110 West Culver Street.

But here is my favorite:

1142 West Culver Street

The bamboo fencing is so demure, providing that added little bit of privacy. Can you see through it? Let’s take a closer look:

1142 West Culver Street — close-up

When we pull away the veil, we reveal… Nothing. The house burned down about 18 months ago. Our friend Jerry Kadansky was the demolition contractor, but the neighbors pitched in by hauling away much of the undamaged material, including every last piece of what was once a very impressive slate roof. But where you see a vacant lot, sees the house it has absolutely no way of knowing is no longer there. Zestimated value: $325,787, again beating out 922 and 1110 West Culver Street.

This is shooting fish in a barrel, but that’s not the point. The point is that, whatever it is that might be doing, what it is not doing — what it cannot be doing — is evaluating houses. This simply cannot be done by the methodology has employed.

The real estate industry is beset by a sea of troubles, not the least of which is the reputation some Realtors have earned by telling lies to their clients. does not tell lies. It simply does not tell the truth. By the nature of its methods, flowing without opposition from its underlying epistemology, cannot possibly, cannot ever, cannot under any circumstances tell the truth.

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76 Comments so far

  1. […] – With automation comes errors or incorrect information – as broken down with pictures and examples by Greg Swann over at […]

  2. […] Bloodhound Blog – Debunking… – By Greg Swann […]

  3. […] cannot tell the truth about home values, so it is releasing an Application Programmer Interface to spread its misinformation far and wide. […]

  4. […] Experience: Zillow offers a map based search of homes, allowing you to learn Zillow’s estimated value of each property. While the idea of easy access to every homes value is compelling, these estimates reportedly vary wildly. Phoenix based Greg Swann recently wrote a lengthy article about the inaccuracy of their “Zestimates.” Regardless of their accuracy, Zillow has NO data on South Bend homes. […]

  5. […] The Real Estate Newsblog takes exception, sotto voce, to to my criticisms of’s epistemology: I guess a significant problem for Zillow at the moment is credibility. Some suggest that Zillow’s “Zestimates” are way off base, but since they’re still in beta, it’s probably slightly premature to be overly critical at this point, notwithstanding the near $60 million they’ve got in seed money. […]

  6. Richmond Business July 31st, 2006 5:31 am

    Greg Swann vs.

    Kudos to a weblog that I have just recently come across (thanks to Carnival of Real Estate) on debunking the all-hailed I have heard a lot of buzz about Zillow, but have never personally checked it out (being a

  7. Greg Swann July 31st, 2006 6:55 am

    Oh, bless you for that!

    The Zillow mystique is analagous to the aura that surrounds the nutritional supplements business. No can possibly confuse a clerk in a GNC store for a physician, but people like the idea of being liberated from the dictates of their doctor while going one up on him at the same time.

  8. […] I wrote Debunking on July 25th, two weeks ago today. Without being arcane or technical, I think it completely demolishes the idea that can — or ever can — provide reliable home values. Nathan Hughes at Richmond Business and Commercial News wrote about my post, and, in a comment there, I said: The Zillow mystique is analogous to the aura that surrounds the nutritional supplements business. No one can possibly confuse a clerk in a GNC store for a physician, but people like the idea of being liberated from the dictates of their doctor while going one up on him at the same time. […]

  9. […] David G. from replied to my post yesterday which argues that Zestimates are bunk, which I had proved to my own satisfaction in an earlier post. I’m revisiting the topic — to everyone’s delight, no doubt — because I want to drive the point home, and because I want to illustrate how a business like could do a better job — which would nevertheless still fall short of’s fraudulent promises. […]

  10. […] What Zillow continues to do extremely well is position itself as the real estate thought leader. Heck, even Time Magazine just named them one of their 50 Coolest Websites. Now I don’t want to dive into the debate surrounding the accuracy of Zillow’s Zestimates, but offering journalists (and by extension, their readers) a fresh, new voice on real estate market – one that dispenses with the stodginess of the old guard – what they’re really offering is one more way to secure their brand’s authenticity and authority in the mind of consumers. […]

  11. […] A Zestimate cannot be “off” or “on”. It cannot be accurate or inaccurate. What is being evaluated is not a house but statistics and documents about that house. As I have demonstrated, the Zestimated house my not even be there. The results can have a greater or lesser correspondence to reality — which attribute is equally true of astrology — but a Zestimate is not a statement about reality. This issue is not whether or not the Zestimate is more or less correspondent to reality. The issue is whether it is wise to substitute calculations based upon statistics and documents about a house for an actual, objective, on-site evaluation of that house. This is a determination an informed party — such as a mortgage lender — can make at his own peril. To induce ordinary haphazardly-informed consumers to do so strikes me as being fraudulent. […]

  12. […] So does this constitute the first official industry endorsement of Zillow’s numbers? Does this mean the real estate industry is prepared to accept Zillow as the final authority on home values? I’m sure Greg over at Bloodhound Blog will have something to say about all of this. No Tags […]

  13. Dan August 27th, 2006 6:11 pm

    Read the interesting blog on “Can Existing Real Estate Brokerages Reengineer Themselves?”

    Zillow appears to be the #1 topic of dicussion everywhere. Why is that when their Zestimates are so poor?

  14. Greg Swann August 28th, 2006 5:29 pm

    > Zillow appears to be the #1 topic of dicussion everywhere. Why is that when their Zestimates are so poor?

    For what it’s worth, that’s not the problem I have with Zillow. The issue is that they represent one kind of information (statistical results from an Automated Valuation Method) as though they were a categorically different kind (a broker’s or appraiser’s opinion of value). If a real estate licensee did this, you would have no trouble recognizing it as fraud and malfeasance.

  15. Gene Whitaker August 30th, 2006 8:59 pm

    Just a quick note about what I saw this evening in I work the Lakewood, CA area extensively. I looked at the value of a client’s home who withdrew their listing in March, citing the “Zestimate” and bad marketing (and no offers). It was about 40K over market. It is now “zestimated” to be up 30K more, while the sales prices in their tract have declined 25-30K below March pricing. (Their re-fi appraiser called me up to ask the particulars of the listing) It strongly appears that Zillow is disseminating fraudulent information to net users to try to run the knowledgeable agents out of the market.

  16. […] And all that will be great. wears a media-conferred halo right now. The more people talk about the incredible, obvious, bone-headed mistakes Zillow cannot help but make, the less people will rely on it — or affect to rely on it. At some point Zillow may elect to tell the truth in no uncertain terms about what an AVM can and cannot do — in order to retain at least a shred of credibility. […]

  17. […] Debunking gets dozens of unique hits every day. Let’s go get sued, a blueprint for bringing litigation against cowbird brokers scores fourth when you search for I think the people at have been very deft in the way they have dealt with criticism. I think Kelman is drunk on his own publicity. The route to fame can be long and uncertain. But it’s just a short hop from there to infamy… […]

  18. […] As a self respecting Real Estate Agent, I never thought I would say this but… lets take a look at Zillow. Before we do though I’d like to make my opinion on the matter clear. Zillow is a very clever website. As an AVM (automated valuation model) for a particular home, I think it’s still lacking. That is to say, at this point, there are too many factors that the website can’t take into account to accurately value a specific home. But I don’t want to get too far on that point, if you really want to read about how Zillow sucks, read Greg Swans Bloodhoundblog (one of my personal favorites) stick it to Z man . […]

  19. Anonymous September 7th, 2006 1:12 pm

    epistemology — wow, good word!

  20. […] Dustin at Rain City Guide is giving stat-dancing lessons today. I am neither as talented nor as interested as he is, but I do have an interesting statistic to reveal: Debunking is averaging well over 100 unique hits a day. All of my extended Zillow rants do very well, and Debunking comes in third if you Google on “” — which many visitors to BloodhoundBlog are doing every day. It pays to keep things in perspective: Our Zillow traffic can’t hold a candle to that which is landing directly on But for anyone looking for a second-opinion, and apparently many people are, it’s right there on the shelf next to the branded product. […]

  21. Don Lieberman September 11th, 2006 1:12 pm

    We have just started a real estate investment business
    we will be buying forclosures, What would you suggest if
    zillow is so far of base, Thanks Donl

  22. Greg Swann September 11th, 2006 6:57 pm

    > What would you suggest if zillow is so far of base

    Realtors comps like this: 1. Tax records (what Zillow uses). 2. Recent sold listings. 3. Active/pending lstings. 4. Visual inspection of the comped homes, as much as is possible. The more you know about the particular homes you’re dealing with, the tighter your comps will be. There are neighborhoods where I can tell you to the dollar what a home will sell for.

    And that’s a possible strategy: Even if you’re not working with a Realtor, you might pay one or more to do tight comps for you when you;re ready to buy or sell. The alternative is a spot appraisal at about $300.

  23. Sheron Cardin September 15th, 2006 6:46 pm

    I currently have Zillow on my website. After reading this blog, should I write a little ditty below their link to take the valuation with a grain of salt?

  24. Greg Swann September 15th, 2006 7:27 pm

    > should I write a little ditty below their link to take the valuation with a grain of salt?

    I’m expect that would violate your license agreement with Don’t worry, though, this one page gets over a hundred unique hits every day. The truth will out.

  25. […] Last place goes to the results produced by an Automated Valuation Method such as or in the Phoenix area. I have written a lot about the defects in Zillow’s methods and practices, as has Sellsius° Real Estate blog. The Cliff’s Notes: An AVM does not evaluate houses, but rather statistics and records about houses. It cannot, for an extreme example, tell you whether the house is still there at the time of the evaluation. […]

  26. Lee Ovington October 1st, 2006 10:06 pm

    I appreciated your examples of how Zillow can badly miss the mark. Take a look at my blog article about my on-going study into the Zillow Valuation Method.

  27. […] Here is part of an post at the Bloodhound Blog with just a couple of examples of why should never be used for more than an evening of fun with friends. “Now, to this point, you could say that this is all so much sour grapes. doesn’t like our listings. Boo hoo! I invite you to pay close attention to the next house, which is not currently for sale: […]

  28. Rich October 28th, 2006 8:31 pm

    The fundamental problem is that the only way to know the value of a home is to record a transaction. That’s why bid-ask spreads are so far apart on any home transaction. Statistically speaking, AVM should be just about as accurate as a realtor’s estimate. By that, I mean that neither will be very accurate at providing a transaction price, but both can and should be used to find an expected transaction price. Bottom line, the sale of a home is incredibly hard to value, because the market for that specific property is thin and illiquid.

  29. Gene Whitaker October 29th, 2006 9:34 pm

    I can’t speak for others, but I can usually determine an offer price for buyers(I love buyers!!!)or listings within a 5K spread. This is done just like an appraisal- i.e. what comp. properties have sold in the immediate area in the last 6 months; what are the particulars of the properties listed and sold; what “sales” in the area appear to be fraudulent (no listing, odd transfers, sellers becoming buyers, pricing out of line with the neighborhood comps., etc.)so they can be ignored; asking the lender to review with a desktop appraisal; and review the other homes listed for sale in the area. You do it the old fashioned way, by doing your homework, and you can get real close to the right price-what the buyer will pay, and the seller will take. There is no magic bullet, you do the work!

  30. […] It happens that I am one of’s most vocal critics. My essay Debunking is the single most popular article on our weblog, BloodhoundBlog. If you Google for, “Debunking” will come up second or third in the organic searches. The gist of that essay is the obvious epistemological point that no Automated Valuation Method (AVM) like can actually evaluate houses — because AVMs are concerned with records about houses, not the houses themselves. The coup de grace in that essay is a presentation of the Zestimate of a house that had burned to the ground. […]

  31. […] Have the cows come home? Is hell freezing over?? Greg has not been shy about saying what he thinks of Zillow’s Automated Valuation Method (AVM) — and I’m not about to spend an hour linking to every one of his Zillowish posts. Here is the “main attraction” For more, just read his blog, you should be subscribed to it anyway, it’s brilliant. […]

  32. Sonja Blocker November 5th, 2006 2:07 pm

    You have all the wrong information on the site My house is appraised by state certified appraiser. It is appraised at 1,200.000.00. has its value at 491,000.00. They are worst than someone with no experience. My house is 3792 sq ft main house with all brick construction. We have 4 large bedrooms 3 baths in the main house.New roof and ac, all new plumbing
    and eletrical. Guest house all brick 550 sq ft all electric, plumbing and air and heat. Two docks on the st johns river which our property is on it 42 feet on the river government maintained channel. We have sprinkler, zoned system. Landscaped yard with gardens , patio, barbarcued areas balcony over looking the river with statley Oaks and moss. Circular Drives and many walkway.
    I am going to contact my lawyer to see the possiblites of sueing you for your lying estimates

  33. Sheron Cardin December 31st, 2006 8:32 am

    I am an interior designer who creates perceived value to resale properties through updating and staging them to model home status. I am also a consumer. The properties shown at the onset of this blog have a perceived value that you are talking about. Zillow is blind? Yes. Perceived value to a buyer is what pulls the wallet out of their pockets. But I have to admit that I would rather pay Zillow’s valuation over the inflated prices that I see.

    Here is my question; Are Zillow’s evaluations ever less than the mortgages on your property listings?

  34. Gene Whitaker December 31st, 2006 11:07 pm

    …”If Zillows guesstimates are ever less than the mortgages on your property listings?” the answer is yes…and no.The point of this blog, and the comments are that the Zillow “Value” is usually meaningless,since it’s uses a flawed formula that gets it wrong about 95% of the time. Values in neighborhoods (especially tract builds)are based on sq ft, conditions and updates.
    For DIY-a RE Agent DOES NOT SET THE LIST PRICE OF THE HOUSE,THE SELLER DOES.The Agent advises a seller of the values in the neighborhood,but the Seller has the final say. But…the price of a home is what the buyer will pay,and be able to get a loan approved for!
    FSBO-Purchase agreement/disclosures needed to buy a home here in CA are 50-60 pages of legal, binding docs.Only a fool(with deep pockets)would try to sell or buy a home by themselves.
    PRICING-If you use the Zillow “value” you will offer too much and wonder why you can’t get a loan approved for that amount,or too little and wonder why you can’t get an accepted offer on your new home. It’s your choice!

  35. Laura Kaan February 11th, 2007 7:52 am

    This was by far the best example I’ve seen regarding the Zestimate’s. Most of us know that they are not always good, but having it in plain sight to see exactly how far off they can really be is great. We’re not talking about thousands of dollars in some examples, but hundreds of thousands of dollars! The ufortunate problem is that many of my cliants will look at Zillow to get a feel for what there home is worth, and I have to tell them why it is not a good idea. Thanks for the information.

  36. […] The business model of simply can not provide accurate market value information, as the public information which it uses tends to lag the market, and most importantly, they are completely ignorant as to the unique qualities and details of each home that it appraises. Has it been remodeled? Does the floorplan work well? Are the bedrooms too small? Are the bathrooms and kitchen well designed? How large is the backyard and is it nicely landscaped? Does the house enjoy good curb appeal and attractive and well maintained landscaping? How well maintained is the home, and does it have any issues such as mold, old roof, or other deferred maintenance? All of these factors are important to evaluate in determining a property’s market value, and simply can not do so. Only an experienced real estate agent or appraiser, taking into consideration all of a property’s unique characteristics can help a client estimate a property’s true market value. Anyone using as fact, may as well be using a Ouija board. Another good web blog that discusses this issue about how is a fraud is […]

  37. […] Others have made reference to’s accuracy. There are problems with delayed updating, wrong information about the specifics of the home, and the inability to see the house and see how it actually compares to those around it beyond comparing square footage and other details. […]

  38. Laura Sutfin March 30th, 2007 1:57 pm

    Hello Greg,
    I was browsing some of your previous blogs and came across your post on Zillow. I think that you’re right on point with their varying accuracy and the consumer’s tendency to assume it is correct.

    I work for a company for a company called HouseFront, that uses text messaging to deliver real estate property values via the cell phone. We offer a rage of values instead of an exact value for the same purpose you inferred on your blog. We are trying to be a Realtor centric company.

    You are a respected blogger on this topic, and we’d like your opinion. Could you please give it a try.

    To use the service, simply text any address to 46873, which spells out HOUSE. Check out the website too,

    Laura: 303.623.5500

  39. Al April 26th, 2007 12:59 pm

    The flap about whether can provide an accurate home value brings me back to the sale of our home 6 years ago.

    Various “qualified”, licensed agents gave us appraisals that came in between $127,000 and $140,000. (small ranch) Everyone of them laughed in our face when we said it was worth at least $150,000. We were told “not in this neighborhood – the people around here can’t afford it.” My wife and I said, this home will sell to someone looking for a starter home from the overheated housing market in the county next door and compared to the prices there for a similar structure, it will seem like a bargain.”

    With great misgivings the agent we decided contracted with listed the home for $157,000. “We can always go down” he said with a sigh.

    It was sold the day before it’s first open house to a couple from the neighboring county with a bid of $160,000.

    Zillow may under value homes, but it can’t be any worse than the “experts” we dealt with in this instance.

  40. […] Debunking […]

  41. […] Does the deal seem too good to be true?  If that’s the case, then it probably is.  Also, be skeptical and realize that some tools are not always accurate 100% of the time.  By compiling impeccable research, you’re dramatically improving your chances of success. […]

  42. […] Another example: Gregg doesn’t use images much at Bloodhound blog so I thought this was quite a find. These are from his famous Debunking post. […]

  43. John Wieland September 24th, 2007 3:25 am

    Finally people in the know are rising up against Zillow, who value my historic district
    house with those (way) out of the historic district, as well as giving equal value to unrestored homes amd those that have been completely restored!! They miss my
    appraisal by over 100,000-and that is an up to date appraisal based on a burst bubble! Thanks Bloodhound!

  44. Robert September 24th, 2007 3:04 pm

    Zillow may not be that accurate, but it does give one a convenient place to look for recently sold house prices and it has a decent mapping feature. What does do for a buyer but give them the rediculous values owners/realtors would like to get. It also has had a lot of bugs recently and does not provide the information in a convenient manner. You realtors have been controlling the market for too long, your commissions are nothing less than outragious and may even be partly to blame for the quick rise in housing prices in the last few years. In my opinion, a sellor or buyor gets little for all the moola they both shell out for those services.
    Robert D.

  45. chris October 3rd, 2007 7:23 pm

    Zillow is a major headache for me when I get calls from customers who think that they can “low ball” offers on homes that are clearly worth what the asking price is.

  46. Wayne Long November 10th, 2007 11:47 am

    I find Zillow to be irrelevant in my area. No one even brings them up. There was a lot of buzz to start with and then nothing. I think is really a bigger problem as people do know them but get poor info from them. JMO

  47. Shari Posey November 11th, 2007 7:30 pm is tremendously successful at public relations. They have gotten press coverage like crazy and it looks like millions in venture capital money from crazy investors. I am so glad I’m not one of those investors because unless can provide some meaningful content beyond listings like it will go bust. Zillow’s Zestimates are a BIG FAT ZERO.

  48. […] For now, CyberHomes is Yet Another Map-Based Automated Valuation Model. Punch in your address and you get a wild-eyed pricing guess based on tax records and statistics and having no material connection to the actual house, which, as I have demonstrated in the past, may not actually even be there. So far: Big yawn. […]

  49. Las Vegas Guy November 17th, 2007 6:08 pm

    Very spot on “devaluation” of Zillow. There should be a huge disclaimer, just like on the TV ads for psychics, “for entertainment purposes only”.

  50. […] But even then, for all but a few hundred Realtors, we are noise in the background. The others see what they see, with Debunking and What’s Wrong with zipRealty? being by far the two most popular hard clicks into the weblog. […]

  51. Bill Gassett November 27th, 2007 6:32 pm

    Greg – I know you have covered the zillow topic endlessly. Whay is most amazingto me is how some of the most intelligent highly educated people see their foolish “zestimate” and actually believe that it is accurate. In my area of Mass, the zestimates are almost always substantially higher than the true value. You would think that with so much press written about them they would at least be working on making their estimates better.

  52. Lee Carlson December 5th, 2007 10:12 am

    I am a Realtor and have my own home for sale. I did extensive market research on my own neighborhood and came to the conclusion that it was worth about $179,000.
    I then looked up the zillow est. and found that they valued it at $158,000.
    I got a full price offer of $179,000. within 2 months. ! So much for Zillow accuracy.! I my opinon, Zillow is so full of misleading info, they should be banned form doing business. They have even shown aerial photos of one section of my subdivision, 2 blks. away from me, that has been built out for about 15 years, and Zillow shows it as vacant land !!
    Please,..don’t waste your time with that site. It will only make you angry !

  53. Asmodeus December 6th, 2007 4:33 pm

    I’ve been reading this article and the discussion quite fervently and based on what I’ve been reading, I’ve formulated a question that has just struck me as odd and I’m wondering if anyone has thought the same or similar thing. Do any of you think the comp system of valuation of homes, be it from appraiser, bank, or website is actually valid or should a home and it’s property be valued on it’s own merits outside of having comps used to derive an apply a value to it?

  54. Vancouver Washington Real Estate Guy December 18th, 2007 12:29 am

    Zillow is just a tool. Many fixers and foreclosures in the are can have a negative effect on home values, the opposite is true for remodeled and new home in the area. Zillow cant look inside a home.

  55. […] What’s the secret? Like this: Relevance equals Title plus Headline plus Body Copy. If those three elements are in close correspondence, to Google the article is what it says it is. If that sounds like a Zestimate of a burned down house, it’s because it is. Software cannot evaluate objectively, it can only draw inferences from trusted indicators. If you leave a trail of indicators that Google associates with highly-relevant content, then it is highly-relevant content. […]

  56. […] We have just started a real estate investment business we will be buying forclosures, What would you suggest if zillow is so far of base, Thanks Donl Learn More . […]

  57. […] new homes is almost a side-effect of this effort. I myself have never been a Zestimate fan — very much the contrary — but clearly there will come a day when close enough is good enough — when the […]

  58. Blogger Spotlight; Greg Swann January 16th, 2008 3:05 am

    […] were just starting to get serious attention when I wrote Debunking That post has a lot of Google-virtues: The keyword “” is in the title and is […]

  59. […] made its reputation, from the very beginning, digging up bones to pick with vendors. And of all the vendors that I, personally, have picked on, […]

  60. Bill in Florida February 24th, 2008 8:09 am

    I have to admit, I am NOT a real estate professional.
    I am just a person who is in the middle of this Real Estate Crisis trying to sell a home.
    I have watched my property go from $1.65MM to a heart breaking $700K. While my agent still has me at a much higher value, there is NO WAY I can achieve his quote. That is, not if I want to sell the property anytime soon. I can tell you that at least where I am located Zillow has been very accurate in true values. Selling prices are as close as 4% in most cases where sellers understand what the market place can deliver. I notice that the people who find fault seem to be agents of sellers. Could it be that they can’t handle the reality of their paychecks falling back to what their services are really worth?? As I see it they are taking the easy way out and blaming the messenger (Zillow) and Not understanding the message.

  61. Shari Posey February 24th, 2008 10:38 am

    I am a real estate agent but I was also a seller last year. Don’t get me wrong, Zillow has some value because it does show what the last recorded sales have been in the general area however it does not show remodeling, upgrades, or additions to homes. In our case, we purchased the home was sold as a complete fixer for $525,000 and we remodeled extensively over two years including electrical, plumbing, a showplace kitchen, etc. At the time we put it on the market, Zillow set the value at $575,000 and it was pulling comps from a neighborhood that was only a few blocks away but not as desirable. Becaues I have access to detail comparables through the multiple listing service and I had seen the interiors of most of the homes on the market and recently sold, I priced it to sell at $689,000 and we actually sold for $675,000 within 3 weeks. Zillow was way off because it didn’t know the condition of our home. In another example, Zillow had one of my listings valued at $850,000 but actually after several months on the market it sold for $785,000. Zillow is a curiosity for homeowners not a tool for professional real estate agents and investors.
    To Bill in Florida, real estate agents tend to be optimists–we have to be to work in this competitive and crasy industry. But it sounds like you need to stand up to your agent or fire him. Usually it is the other way around, sellers want to keep the price high at the agent’s recommendation of a reduction.

  62. […] up with We’re consistently second or third on a Google search for, and Debunking is one percent or more of our traffic every day. On the other hand, we’ve also been big […]

  63. […] up with We’re consistently second or third on a Google search for, and Debunking is one percent or more of our traffic every […]

  64. […] The bottom line: while zestimates are fun for zillowing your boss’s home, it is not a tool that you should be using to determine the sales price of you home, or the offer you should make on a home you wish to buy. There is only way to do that, and that is to use a real estate professional that has access to local, property specific, and comparable home information. Greg Swan, a top real estate professional in Arizona, has done a great job of showing just how out of touch Zillow is with reality at his blog. […]

  65. […] The bottom line: while zestimates are fun for zillowing your boss’s home, it is not a tool that you should be using to determine the sales price of you home, or the offer you should make on a home you wish to buy. There is only way to do that, and that is to use a real estate professional that has access to local, property specific, and comparable home information. Greg Swan, a top real estate professional in Arizona, has done a great job of showing just how out of touch Zillow is with reality at his blog. […]

  66. Sue March 30th, 2008 8:06 am

    I am a realtor and have had several clients bring up Zillow as a reference. My feeling is that its interesting, but not accurate. Zillow may hit the target once in a while, but more often it provides a wide ballpark for buyers and sellers which a realtor can use as a starting point for the conversation to talk about comps both sold and active in the area and varying factors.

  67. […] is a popular tool that some buyers may be using to price home offers but be very, very careful.  I recently looked at the comps Zillow had for a property some clients of mine were purchasing.  […]

  68. Cheryl Stimac April 28th, 2008 11:29 am

    I don’t hear much in the Tampa Florida market about Zillow. It doesn’t appear to me that many of the prospects I deal with are using it at all as a valuation tool. Just another automated process that is about as accurate as anything else done in a vacuum instead up close and personal by a trained and experienced local Realtor or Appraiser.

  69. Sue May 20th, 2008 8:43 pm

    I had someone refer to Zillow again the other day. I believe it to be a bad tool as its inaccurate and makes my job harder if Zillow is putting a higher than deserved price on the home. Some understand that there are other factors, some want believe the higher estimate.

  70. Cash Back Real Estate June 26th, 2008 10:51 am

    It is a tool that can be useful though it is best to use a licensed appraiser who can inspect the subject property and properly analyze the local market and comparables. You always need someone who can inspect the subject property.

  71. Larry Romo September 11th, 2008 1:07 pm

    Unfortunately there is actually NO ACCURATE valuation service in existence. Zillow is just a guide line, like all the others, no better, nor any worse.
    An example, I just had my home appraised by a professional appraiser for the purpose of getting a refi. This supposed professional appraiser could not even figure out where to look to find out if it was actually a land/home package which I owned or if it was a mobile home on a leased property. I had to send him the county records to show the property and my ownership thereof. These were just copies of publicly available data available to anyone with an internet connection. This “professional” did not have a clue. Then to top things off, I had to provide him with comparable local sales for him to base his appraisal on. Then he proceeded to appraise the property for 75% less than what I could sell the property for even in today’s trashed market. If I were to list it at the price he quoted in his appraisal, it would be sold in 1 hour to the listing real estate agent or their brother. Because they would know they could flip it for double that in a few weeks time.
    There is no such thing as an “Appraisal expert” and any estimates of property value should actually be termed “Guesstimates”.
    Is there any regulatory agency controlling appraisers? If so, and if I can find out this idiots license number I will be filing a complaint of gross incompetence against him. Maybe he’s just doing supper low appraisals so he can buy the property and flip it?

  72. carlos meza October 9th, 2008 1:16 pm

    I use zillow to see recently sold homes, only. The information on the recently sold home such as date and price cannot be adjusted. there is a small difference in price for closing and such. But, don’t take zillow as fact. certainly zillow cannot look inside homes to see if they have granate countertops or upgraded fixtures.

  73. […] The bottom line: while zestimates are fun for zillowing your boss’s home, it is not a tool that you should be using to determine the sales price of you home, or the offer you should make on a home you wish to buy. There is only way to do that, and that is to use a real estate professional that has access to local, property specific, and comparable home information. Greg Swan, a top real estate professional in Arizona, has done a great job of showing just how out of touch Zillow is with reality at his blog. […]

  74. Eric M January 26th, 2009 2:38 pm

    It’s especially bad for condos. Most of the condos in my part of Chicago don’t even have the number of bedrooms or bathrooms listed in Zillow’s description, let alone square footage. Br/Ba counts are pretty critical to even start a price estimate, and square footage can give a nice basis for certain areas.

  75. BF March 6th, 2009 7:30 pm

    I took a look at Zillow to see what they thought my house was worth….they zoomed in on what was supposed to be my house but was a neighbors! My house is located behind the neighbors on 2 acres and we have spent thousands on plants, trees, and landscaping. When I saw the picture I about was before they had even landscaped, no sod, no trees, no driveway! How do they account of all of the bells and whistles we added to the inside of the home (like the 11.5 x 22 ft. mancave upstairs with a home theatre, etc.?).

  76. Paul March 7th, 2009 10:26 pm

    it does give one a convenient place to look for recently sold house prices and it has a decent mapping feature.

    Zillow is weak on what an indivudal home is worth cause so many factors,they can’t see inside a house.

    But as tool for what recent homes sold in your neighborhood/town it great.It is a good general median home price estimate in your town..