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BrokerSteveO's RE Blog

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By Steve Ornellas | Broker in Fremont, CA

MLS Data Accuracy; Where to search if you are

Since late 2008 I have been a member of my local Association of Realtors® (AOR) MLS Committee;  and as of 2012, a regional multiple MLS Committee member. These MLS Committees basically review/add/remove/modify MLS rules, aid in the “care and feeding” of the MLS as well as vet 3rd party vendor technology for possible use by its Members.

I often see questions from Trulia users asking about the best place to look for property listings, the actual physical address of a property they found on the internet, and the infamous "too-good-to-be-true 2,500 square foot home listed for $9,568 in a great school district".

The primary reason these types of questions occur is due to "listing syndication", and if you want access to accurate MLS information there's only a few sources you should be using!

AOR Basics

When an AOR is formed in a defined geographic area a MLS database software platform must be decided upon (there are a few handfuls of standard software providers for this). After establishing an individual MLS system, any number of various AORs may decide to share information between them. RETS (Real Estate Transaction Standard http://www.rets.org/about) provides protocols/rules for this type of data exchange.


Listing Syndication

Trulia, and other "3rd party MLS listing services" are not AORs; however, these companies do negotiate RETS "data feed agreements” (DFAs) with AORs (who actually own the Listing data) so they can present this information on their own company-branded websites. This is the definition of listing syndication.


In fact, Trulia has negotiated DFAs with many AORs systems, but it will be some time before one can comprehensively rely on the data. You see, some AORs agree to these 3rd party DFAs, others do not, and this is where data comprehensiveness and accuracy can suffer if you are not working with a Realtor®. In cases where an AOR does not agree to a DFA, many syndicators allow agents to still manually upload listings to their 3rd party sites. If not managed diligently, old listings can remain on the syndicator’s sites, misleading those users who rely on this potentially inaccurate or outdated information.


Public Syndication

Another issue arises from “Public Record” listing providers. RealtyTrac is one of the most well-known. I have lost count of the number of times I have had to inform home seekers about RealtyTrac’s misleading (my opinion) data feed on Trulia. RealtyTrac is not a “Distressed MLS”; they simply syndicate public record filings and tease you with them so you will pay them a monthly fee to get more information. Many times these “listings” are not even being offered for sale (See: http://docs.Steven-Anthony.com/RealtyTrac30.pdf). The truth is that most foreclosures are listed on AOR MLS sites - at market value, not the ridiculously low prices shown by RealtyTrac, which may be nothing more than the amount(s) in default, not the price they are being listed at for sale.


Note: To remove all RealtyTrac “foreclosure” listings from your Trulia search results go to your search results page. Check out the Refine Search box on the left and scroll down to 'Listing Type'. Uncheck the 'foreclosure' selection and your search will update automatically and filter out all RealtyTrac listings.



Looking for true MLS Data Accuracy?

If you are not working directly with a Realtor® the most up-to-date comprehensive information source available IS http://www.Realtor.com because it pulls its data directly from just about all nationwide AOR databases EVERY 15 MINUTES. Back in June of 2009 I contacted the NAR Liaison to Realtor.com who unofficially estimated 99% of all AORs had direct Realtor.com feeds (I followed this up with the VP of Industry Relations for Realtor.com who did not disagree with this estimate).


Once a property goes Pending or Sold it does not show on Realtor.com (see most recent update at bottom of the page -- new version released 11/2/12 and SOLDS are now available) ; however, other sites not directly tied into the AOR databases via a DFA will show properties as Active when in fact they are Pending, and in some cases, even Sold. While Realtor.com is the most comprehensively accurate source if you are not working with a Realtor®, up until 2011 when it released its iPad app (followed by iPhone/Android), some basic features were behind the user development curve when it came to functionality; however, steps are now measurably headed in the right direction again.



In a nutshell, your best source for up-to-the-minute information is a local Realtor®. Once you select this individual I would HIGHLY recommend you have them set-up an automated "MLS Search Agent" so you get notifications matching your specific search criteria automatically via email as soon as they are made available. Make sure the Realtor® you decide to work with is either a member of the AOR where you are searching for a home or at least has full access to the target MLS data.

5/10/2011 Update:
Trulia has just released a whitepaper covering information gathered through an analysis of more than 430,000 listings Trulia received from syndicators, franchisors, brokerages, agents and MLSs between February 15 and April 15, 2011. 
One of the three key findings was that listings from syndicators, such as Trulia, had a 21+% error rate in either price or status if the data did not originate from a true MLS source. The entire report can be viewed @

 Trulia is now working on launching “Trulia Direct Reference” which checks 20 listing attributes (price, status, etc.) to update and correct listings placed on their site by agents within an AOR where Trulia does not have direct MLS access.

10/4/2011 Update:
Trulia blog: "Mo Homes for Sale, Mo Problems"
"Finding homes to buy and sell today is pretty easy thanks to the Internet, but as for making sure all the need-to-know info (that’s been posted online) is correct – not so much."

3/11/2013 Update:

Inman News: "Realtor.com launches redesigned website"

4/19/2013 Update: Inman News: "Realtor.com marketing campaign zeroes in on listings accuracy"  'Find It First' ads suggest buyers could be at a disadvantage if they use third-party sites"


By Carl Medford,  Wed Jan 26 2011, 15:39
Great information - thanks!
By Pacita Dimacali,  Wed Apr 13 2011, 11:32

Tell them...then tell them again...and then tell them again!

By Steve Ornellas,  Wed Apr 13 2011, 15:16
I read a person has to hear something 3 to 5 times from 3 different people to finally have it sink in.
Thanks for helping point the public in the right direction.
By Carlos Escamilla (305)240-6896,  Fri Sep 2 2011, 21:25
Wow it take a lot of experience and time to archive so much information.
Thanks now I have more tools like you said to advise all disoriented homeseekers who believed on realty track prices.
By Steve Ornellas,  Tue Sep 6 2011, 15:36
Hi Carlos, spread the word.

By the way, http://www.realtor.com released its new mobile app where you can perform geo-bounded searches with your finger right on your smartphone screen. Might come in handy if you are out and about and need to find other listings in the immediate area.
By Bernard Gibbons,  Fri Dec 16 2011, 08:01
Great article, Steve. And yes, I have the Realtor.com app on my Droid. Very useful and accurate.
By Timothy M. Garrity,  Fri Dec 16 2011, 08:22
Great information on the MLS. Thanks for posting.


By Steve Ornellas,  Fri Dec 16 2011, 08:56
@ Bernard:

I have it on my Droid as well (reading glasses required!) You can sure see (no pun intended) how a tablet would come in handy ;-)
By Steve Ornellas,  Fri Dec 16 2011, 09:01
@ Tim:

Spead the word!

I have to admit that Realtor.com still does not have the best user interface out there (they are heading in the right direction); however, I'll take their "accuracy" over "cool" any day.
By Gary & April Greer,  Sat Sep 8 2012, 10:59
Great post. We have been using Listing Book for our clients and they really seem to like it. So far the accuracy has been spot on as well!
By Steve Ornellas,  Sun Sep 9 2012, 08:54
@ Gary + April:

Yes, mine too! ListingBook has a direct data feed from their respective MLS partners. In my area I have had to supplement with additional MLS search Agents due to out-of-area agents listing in the local areas I serve, however.
By Kerry Lucasse,  Sun Nov 4 2012, 18:56
Great explanation --- I wish we could all repost this on our blogs to spread the word to buyers and sellers.
By Ken Allen,  Sat Apr 20 2013, 11:39
Good information. Thanks.

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