…that 9 of 10 buyers find real estate listings on-line? Popular sites like Zillow, Cyberhomes and Redfin don’t always get it right, though. One study showed that Zillow estimates overvalue property by 10 percent compared to the sales price. If you go to the new Zephyr website (ZephyrSF.com), you can view the real data and right next to it the Zillow and Cyberhomes estimates. If you click on “tell me about these estimates” you get a table of the recent sales and how each estimate did in comparison. You even get a quick explanation of the accuracy of “Automated Valuation Models”.