How accurate do you think Zillow, Cyberhomes, and Trulia are at estimating home value? (disclosure, square footage)

[JamesandSallie]

I am very curious as to how accurate (if at all) you think these websites are at estimating home value - in addition to looking at comps, etc - would you use the values from these websites in helping you determine how much to offer for a home?

Thanks!

[TexasHorseLady]

It depends. In a nondisclosure state such as Texas, not very. In a state where they can get the sales information from the same public records as anyone else can, as they are public record, they can be pretty accurate except that they aren't using real comps (I've seen comps that are in entirely different kinds of neighborhoods clear across town that bear no relation to the actual property because they don't know what's going on inside of it, for example, as they don't have access to that information).

So, my definitive answer is: it depends. Sorry not to be able to be more helpful.

[chet everett]

Using it to locate comps is fine, heck with the MSN LIVE maps and google streetview and photos and other info it beats the pants off MLS. If you understand where they source the info from (mostly other third party records providers...) you quickly understand how / where errors crop up. If you have moderately deep knowledge of the area you are scouting, and can verify info in MLS or the real government sources, it can be a time saver.

BUT the algorithms they use to assign value are way out of whack. Too much weight given to most recent sale / distance and virtually NOTHING given for age / size / condition. They often have boundaries / schools / tax districts completely WRONG. That alone makes it worse than useless -- if it tells the "closest" school is one in a district that the kids would NOT attend buyers could potentially overpay by a massive amount, in fact this happen to a whole neighborhood near me, and wiped out the immigrant developer types that built grossly overpriced home in the wrong school district. OUCH!

The other thing that I hate about the auto estimators is that I can (and sometimes do) know tricks to inflate or depress an area by adding or incompletely 'updating' details. Potentially VERY damaging.


They are something in my toolbox, but like the GIANT screwdriver that I use not to drive screws, but as a medium-small wrecking bar, I use 'em for a purpose that is not really "as designed"...

[MsFancyPants]

I hope it's accurate, because I just got an email from them that my condo INCREASED in value by .6%!! I'll take any increase!

[tambre]

Zillow has stats for my house that are totally wrong....square footage, number of bedrooms, etc.

[rubber_factory]

I agree with chet, good post. There are some very important school district boundaries in my area that zillow and trulia both screw up. Square footage and bedroom values routinely have strange data errors - i.e. 0br 3ba, 5000sqft ? Not to mention that even if they had accurate data, they are still taking on an impossible task, attempting to build a nationwide valuation model based on data. My career involves building similar types of geographic models, and sometimes the task just contains too many variables that cannot be measured, or not easily measured.

I think they are accurate, give or take 40%.

[emilybh]

It used to be that Zillow was notorious for underestimating. Now their lowest "zestimate" is often a lot higher than what the home sells for. I think Zillow needs to use its own "Solds" info to re-adjust the "zestimates".

[AONE]

I don't find them accurate here in central FL. seems like a busy exercise and nothing more. Better off running comps

[MsFancyPants]

Buzz killers!

LOL!

[middle-aged mom]

Zillow and the like, are not inside of homes. They don't know the condition or the floor plan. They do not distingusih between better and inferior locations. And they don't know why a home sold for what it did, when it did.