BEST ANSWER
A Realtor's CMA can include information that's not in the public records, and can be fine-tuned to better reflect your property's home.
For example (and I'm more familiar with Zillow and RealEstate ABC's calculations than I am with Trulia's), often you'll find that so-called "comps" aren't really. The worst I've seen is comparisons of 3 bedroom condos to 3 bedroom single-family homes. And comparing properties built 5 years ago with those built 50 years ago. Admittedly, a good automated system should be able to eliminate those non-comparables, but all too often they seem not to.
The automated systems also don't take into consideration the condition of the homes. You can have two homes in the same neighborhood. One hasn't been upgraded in 25 years. The other has granite countertops, stainless steel appliances, etc. A Realtor can look at the listings that sold to determine true comparability and to adjust values as appropriate.
Most automated systems just work on a geographic basis. It's true that comps should be nearby. But, for example, I live in a nice middle-class neighborhood. However, there's a connecting neighborhood that is more upscale. Home values are about $100,000 higher there. But if an automated system doesn't recognize the difference between "Colchester Hunt" and "Fairfax Hunt," then you won't get accurate comps.
Also, consider a house that "sold" for $300,000, according to public records. An agent can go into the MLS and see that although the house "sold" for $300,000, that there was also a 3% seller subsidy, or a de facto $9,000 price reduction. So the true value of the house was $291,000, not $300,000.
A Realtor can also present a CMA to best reflect what the seller or buyer is looking for. For instance, suppose you as a seller want a fairly quick sale. You want the best price possible, but you do want to sell promptly. A Realtor can look at "days on market." For example, maybe the automated comps say that houses like yours sold for $300,000. But it won't tell you how long it took. Suppose it took an average of 120 days for homes priced at $310,000 to sell for an average of $300,000. A Realtor might advise you to price yours at $290,000 if you'd like to sell it a bit quicker.
A Realtor also can look at houses under contract. True, solid comps are those that sold. But, continuing with our example above, suppose there are 3 houses under contract and they were listed for an average of $290,000. Assuming they're not foreclosures (or other odd conditions, and a Realtor can determine that), then the actual contract price is likely to be slightly lower--say $280,000-$285,000. So even though the automated comps might say $300,000, a Realtor might know that homes now under contract are selling for 5% less. And a Realtor can actually call up the selling agent and try to find out what the contract price was. The selling agent doesn't have to provide that, but they sometimes will, or they'll provide a helpful range. That's not something any automated system is able to provide.
Similarly, a Realtor can look at homes that were listed but were withdrawn, or expired. With the example above, let's say there are a few homes that were listed at $300,000 but the listings expired. That'll never show up on the automated systems--how can it?--but it'll tell the Realtor that similar houses priced at $300,000 didn't sell. And so, likely, neither will yours.
I could give you half a dozen other examples of how Realtors prepare CMAs that offer distinct advantages over the automated systems. The point, though, is that even though the automated systems provide some value, and are fun to use, if you really want an accurate CMA, you need to use a Realtor.
Hope that helps.
Sat Jul 25 2009, 14:09
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