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Replies (3)

- debk007
- Contributions:5
I agree, when I looked at other home values on the same street as my house, some of them went up in value in the same 30 day time period while mine went down. I'd like to know how Zillow is calculating these estimates since it doesn't seem reliable when I look at other homes in the area.

- Tanya Ericksen-Troska, "TanyaEricksenTroska"
- Contributions:54
The "secret recipe" is a special algorithm that Zillow uses to put together a calculated guess of pricing based on patterns in a particular market area. It is NOT an appraisal nor a CMA, which will look at a more defined area; especially those niche communities, nor will it look at popular styles or even property conditions or street appeal. It is strictly numeric equations. So, the more data that there is available, the more those Zestimates adjust... sometimes, fairly; sometimes not so fairly. For example. A few years ago, my own home would have been priced a bit higher; comparatively to other like homes in my neighborhood. However, since then, we've added a second story, and have done some remodeling. And, although, there are other 2-story homes to compare to, there isn't enough reportable data by 3rd party sources to budge my Zestimate. Therefore, today, my own personal home's Zestimate is completely off-guard from other like homes nearby. As a homeowner you can make adjustments to your home's description and adjusted values, and that will be shown as your personal thoughts of pricing on the home's profile. But, at the end of the day, the market will dictate value. And, who determines is the "market value"... well in addition to tighter legislative restrictions on bank appraisals, the buyers really determine value. And, who's closest to that market knowledge? Those that work it every day. So, talk to real estate professional, or get an appraisal, and then take a deep breath, look at it from the perspective of a buyer, and go from there.
For more information on Zestimates visit: http://www.zillow.com/wikipages/What-is-a-Zestimate/

- Erik Pearson, "SpringHillHomes"
- Contributions:36
I've been reading about zestimates with a lot of curiosity, and just had a light bulb go off. If zestimates use an algorithm that is supposed to learn, why don't they ask agents all over the country to give price opinions on homes so that the program can learn from actual agents in the field. So far, I haven't read anywhere that this is being done.
I think the Zestimate formula needs a few "eyes of newts" to quote your secret formula ingredients.
Your Zestimate cut my home's value to less than half in a day because one of my neighbors, whose home has been on the market at an outrageously over inflated price for almost a year, finally took 10% off (not enough) their crazy asking price. There is no way that my house is worth less than half the value you had for it a few days ago. Thanks Zillow for single-handedly screwing with my neighborhood's value through your fabulously flawed "secret formula." Yes, housing is still in decline, but not that steep in my neck of the woods.
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