After some discussion, I signed up for the trial, largely because other web sources of similar information seem to be less good (in some cases, completely useless crap). Our calculation is that even paying a year should be damn easy to get back if it helps us determine the right time/property to buy and the right amount to offer. RealtyTrac is awesomely cool and a major time suck, altho I could wish that their search page was a little better. You can search by zip, city, county, but not list-of-towns, so I'm either stuck laboriously doing several searches per town, or sorting through a bunch of cities I don't want on a county search (and then doing a second search for Harvard, which is in Worcester, not Middlesex county). I also wish that you could sort finer on square footage.
They offer some loan and prior sale information, but it is freakishly tricky to decode. In some cases, you can just see the ATM behavior in action, but in others, the refis are scattered 2/decade at erratic amounts, some up, some down and it isn't always clear if these are replacement loans or additional loans in all cases. And I apparently am still sufficiently naive in the ways of real estate that I don't understand the various kinds of sale. But I will!
We expect we'll still get an agent at some point, but this should help us figure out which agents are shining us on.
Zillow.com, of course, is free. Where Zillow at the height of the bubble had prices that struck me as consistently 10%+ too high, now Zillow has prices that are, well, let's just say they knock more than 10% and/or $100K off of some of the houses we have been contemplating. Best of all, Zillow includes (usually) some past sales information and (as near as I can tell, always) a chart of past valuation for the home/area/etc. Which means you could, in principle, pick a date where you think we're going back to, and use that for valuation. Nominal/real dollar problem, not to mention there's the talk-the-lender-into-playing-along issue (assuming you can get the "owner" to agree), but still.