ZipRealty and Redfin Integrate with Zillow’s API
By: Mark Eamer, Director, Online Marketing | October 16, 2006
We are happy to report today that both ZipRealty, a national full-service real estate brokerage, and Redfin, an online real estate brokerage with listings in Seattle and San Francisco, recently integrated Zillow’s functionality into their Web sites by using Zillow’s API.
With ZipRealty, customers can compare the price per square foot of the home based on the list price, the Zestimate valuation, and the average of nearby homes for sale — all in one central place. This information can be useful to get an initial feel for how the home’s list price compares to the estimated value of the home from Zillow as well as from other recent home sales.
Redfin now displays Zillow’s Zestimate, Zestimate ranking and a Zestimate value change chart for every listing alongside the photos, marketing remarks, amenitites, past sales and historical tax information. Tying Zestimate functionality to their newly released “fixer-upper” algorithm will enable people to quickly segment Redfin listings and search more efficiently.
It is our hope that both of these companies will make consumers’ lives easier by combining listings with Zestimates. Consumers will no longer need to have a second browser window open, feverishly typing an address into Zillow.com, in order to get a starting point for a home’s value.
Remember, our Open API will be launching soon, but if you want to get started coding today, feel free to sign up for our API program. We’ll process your request ASAP and you will be among the first to know when the Open API launches.
Our API program is now live — you can access all the relevant information from our landing page.
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- Categories: Real Estate, Zestimate, Zillow, Zillow API
Comments
3 Comments so far
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Art Avendano on October 18, 2006 10:40 am
My home is 9028 SW Grand Canal Drive, Miami, FL 33174.
It appears on your site for $384,087.00 while the same home with less sq. ft. a few houses over shows up for $415,164.00. That address is 8964 SW Grand Canal Drive. Why is this shown this way?
AK on October 18, 2006 4:44 pm
I think in the current market, Zestimates are on high side. My question is is there a way to validate your Zestimate?
Zestimate should be what a house sells for.
here is one approach:
you show the differences between the Zestimate and actual sale price of the houses sold recently. if average for this difference is always positive it means your estimate is higher than market value. in ideal situation, it should be close to zero.
David G from Zillow.com on October 19, 2006 2:00 pm
ART -
Since we don’t have a lot of sales history for both houses, the Zestimate algorithm starts to rely more heavily on the difference in the tax assessor’s relative opinion of value which is reflected in the variance between these two Zestimates. You can see tax assessed values on both house’s details pages.
That said, the value range (below the Zestimate) for both houses overlaps - these Zestimate’s ranges aren’t that different. I’d guess that the market value for both houses lies somewhere in this overlapping range - i.e. from $348K to $434K. FYI - A large value range indicates low confidence in absolute accuracy of the Zestimate.
Accuracy in your neighborhood will increase as our database of closed sales transactions grows. We’re also working on enhancements to the math that picks similar homes - I hope you notice an improvement with time. Thanks for your feedback.