Image: Home for sale © Seth Joel, Photographers Choice RF, Getty Images

It used to be a given for anyone selling a house that a real-estate agent would put the listing on national real-estate aggregator websites like Zillow, Trulia and to maximize exposure and sell the home quickly. But that could be changing fast as aggregators and agents face off.

Since 2005 or so, real-estate agents have shared data about homes they have for sale with those national sites, which have millions of visitors (Zillow, for example, had 32 million last month). But even though the sites have grown, sales haven't in the distressed housing market, and some agents believe the sites may not be helping. They accuse the sites of engaging in practices that give buyers inaccurate information that may hurt sales.

Among their complaints are that the sites allow any agent, for a fee, to have his or her name and photo appear prominently beside the homes listed for sale in a given region, even if the person in picture isn't the agent representing the seller. In reality, the agent in the photo may know little about the property or the neighborhood where the house is located, frustrating customers' efforts to get accurate answers, according to a report last year by real-estate consulting firm Clareity.

Some agents also claim that many listings on the largest sites are inaccurate. "The wrong photos often appeared with our listings," says San Diego Realtor Jim Abbott, whose firm no longer shares data with the national sites. He also says that the sites kept up listings that were no longer on the market. Clareity CEO Gregg Larson says Zillow and Trulia get information about the same property from multiple sources, such as the listing agent, the local multiple listing service and syndication services. "The duplicates sneak through, and then you have (the same) listing with different prices, listed by different brokers."

One Massachusetts agent, Jack Attridge, notes in a letter to Inman News that because homes he's listed appear on national sites, he's often contacted by agents and customers well outside his area who have questions about those properties. Most of the time, they have incorrect information, and Attridge wrote that none of those calls has resulted in a sale.

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These and other problems hurt agents' reputations and do nothing to sell houses, they say. Abbott argues that inaccurate Web listings, combined with side-by-side links to agents who know little about the property, frustrate potential buyers and may actually drive them to look elsewhere.

Abbott studied three years of his agency's sales data and compared listings that the company didn't share with national sites to those it did. "Time after time, the listings that we did syndicate compared with the listings that we didn't had no better outcomes," he says. "In fact, the ones we didn't syndicate often sold faster" and closer to the asking price.

Zillow CEO Spencer Rascoff has fired back, asserting that an internal company study shows that homes in the top 10% of page views on Zillow sell more than a month faster than their counterparts in the bottom 10% of views and achieve sale prices closer to their asking price. He also says Zillow "invests massive resources in making our listings as accurate as possible."

Nevertheless, Abbott and a few others have opted out. Edina Realty in Minnesota fired the first shot in November by announcing it would no longer list its data on aggregator sites like Trulia and Abbott pulled out on Jan. 27 with a hard-hitting Web video announcing his company's plans. Then on Feb. 6, a bigger player weighed in: Metrolist, a Denver multiple-listing service (a member cooperative that agents jointly buy into that advertises properties locally), announced it would no longer allow a Zillow subsidiary to use its data.

Some agents in larger metropolitan areas say they have better local listing service options. "It would only take a few good-sized brokers in every community before these sites either drastically changed how they do business or went away altogether," says Abbott.

But other industry insiders worry that agents will lose business by pulling out of the aggregator sites. "All it takes is (brokers who don't share data) losing a few listings and having a couple of their top-selling agents complain," Larson says, and "they'll cave."

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Jay Thompson, the owner of Thompson Realty in Phoenix, has chosen to continue listing with the sites. "Good luck explaining your decision to not market a listing on high traffic sites," he writes on his blog. "I can assure you that if a Phoenix area brokerage chooses to do that, then we will use their decision to our advantage."

Abbott argues the opposite could happen. Since he posted his video, he's had 12 people who were interviewing for an agent to sell their home ask him about his company's new policy. "We got all 12 of those listings," he says. Calls to the company, he adds, have "gone through the roof."

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