It is possible for homeowners to determine the estimated value of their homes by checking Web sites online. Testers attempted to find out whether the various house-value Web sites generated consistent figures. Testers obtained five estimates in all, four from online sites and one from a professional, human appraiser who inspected the relevant home in person. The figures ranged from $291,000 to $375,000, a difference of $84,000 in estimated value. Part of the problem in receiving estimates is that some Web sites only provide a broad price range and require users to request a contact from a real estate agent to obtain a more specific figure. These sites appeared to be tools for agents to build up their prospect lists, and they probably contributed significantly to the wide difference in home-value estimates. Testers found it was difficult to obtain an instant, single quote from sites that advertised providing free figures. And it was difficult to obtain estimates without giving out personal information and a telephone number and e-mail address. Users are often required to agree to agent solicitation as well. Real estate agents pay the sites for leads, and then they calculate an estimated value for a home as a way to get business. Two sites resolved the problem by offering price estimates for any address without requiring identifying information. These sites were realestateabc.com and zillow.com, a Seattle startup firm launched in early 2006 by former executives of Expedia.com.