A report commissioned by property search company Roost found that property information can vary widely in volume and accuracy among online sites, with some sites showing a small fraction of the for-sale properties in a given market area.

A report commissioned by property search company Roost found that property information can vary widely in volume and accuracy among online sites, with some sites showing a small fraction of the for-sale properties in a given market area.

Prepared by WAV Group, a real estate consulting company, the report found that some online sites are missing a majority of the properties that real estate professionals have listed for sale in industry-operated multiple listing services, and that property information at some online sites is far less accurate or current than broker-shared property data derived from area MLSs.

The study focuses on a range of online sites that offer property search tools for consumers, including Google, Roost, Trulia, Yahoo and Zillow. Site comparisons in the study are based on searches conducted for single-family resale homes with exactly three bedrooms and two bathrooms in three market areas: Dallas, Miami and San Diego.

Additionally, different price points were selected in each of the market areas in an effort to equalize sample sizes of search results within each market area to about 100 homes. Searches were performed on each site on the same day within "as short amount of time as possible," WAV Group reported.

"The data here clearly show, as they did in a national study we conducted earlier this year, that a site based on information from a local MLS will give consumes a more accurate picture of what’s available in a local market," said Victor Lund, founding partner of WAV Group, in a statement.

Sites based on MLS data have upper hand

The study concludes that third-party sites that do not rely on MLS listings or Internet Data Exchange (IDX) sharing agreements among brokers "are still struggling to collect a comparable, comprehensive data set of accurately displayed listings."

That conclusion is perhaps not surprising, given that the report is promoted by Roost, which operates a search site powered by IDX information from numerous market areas.

"Until now, very little research has been done on listing accuracy – a key demand of today’s online shopper," the report states. "Understanding that Web sites get their listing information from a variety of sources, we were interested in knowing the differences."

The most accurate source of listing information is the local MLS, the report concluded, though not all MLSs offer a publicly accessible search site for properties listed for sale in the MLS.

Realtor-affiliated MLSs do allow member brokers to set up publicly accessible IDX sites through which they can share property information with one another.

"WAV Group research established that searchable housing information on IDX-powered Web sites is the most accurate public home search available – usually 96 percent to 98 percent accurate," the report states.

While some brokerage companies and MLSs choose to share property information with a variety of third-party sites, others are guarded about such distribution agreements.

Third-party sites face ‘awesome challenge’

WAV Group reported that in Dallas, Google displayed about 69 percent of the for-sale listings that could be found in the local MLS, with other third-party sites, like Trulia, Yahoo and Zillow, carrying a smaller percentage.

In Dallas, the local MLS and Roost and an IDX-based Century 21 brokerage site ranked among the most accurate and comprehensive search sites. In Miami it was a similar story, with sites based on MLS data and broker-to-broker sharing agreements ranking the highest and third-party sites ranking lower, with fewer for-sale listings.

"Clearly brokers and agents are looking to promote seller listings online in the best possible way to reach as many buyers as possible. Unfortunately the process in place today for getting accurate and complete listing information to third-party Web sites is an awesome challenge," the report states.

While many real estate Web sites refresh their data each day, just as IDX sites typically update within 24 hours, many of those sites "underperformed the IDX-powered Web sites," the report states, by displaying a fraction of the for-sale properties listed in the MLS.

Searching in San Francisco

Inman News on Tuesday afternoon conducted searches for San Francisco homes at a variety of real estate search sites to compare the results.

The search queries sought to obtain a list of active for-sale homes in San Francisco. No property criteria were selected to narrow the list of for-sale homes, unless cited.

The individual properties in the search results have not been tested against the local MLS data of for-sale properties, so it is possible that some of the properties are no longer for sale or that they may not be listed in the MLS or may be duplicate listings, not within city limits, etc.

Here are the results from the comparative searches of for-sale homes in San Francisco:

San Francisco Multiple Listing Service: 2,420 properties. The search included single-family properties and condo, co-op, loft and tenants-in-common properties.

C21.com: 270 properties.

Estately: 1,699 properties. The company reported 237,100 total properties for sale.

FrontDoor: 2,239 properties. The company reports a total of about 3 million properties at the site.

Google Base (Google’s online classified site): 2,454 properties. The site lists 2.91 million total for-sale properties.

Intero, a Silicon Valley-area brokerage company: 2,620 properties.

Realtor.com: 2,166 properties. The company reported 4.6 million for-sale and rental properties.

Redfin: 1,661 properties.

RE/MAX (remax.com): 2,162 properties from multiple associations/MLSs. The company reported over 4 million for-sale properties.

Roost: 1,935 properties. The company reported a total of 1.36 million properties at the site.

Trulia: 2,592 properties. The company reported 3.5 million total for-sale listings.

Vast: 2,526 properties, from 162 sites.

Yahoo Real Estate: 1,010 homes for sale. The site advertises over 3 million homes for sale and for rent.

Zillow: 1,200 properties, not including "Make Me Move" properties. The company reported 3.11 million total for-sale properties listed.



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