Real estate advice: Development's prices fall just before closing
I found this link at The Volokh Conspiracy. It goes to a Bankrate.com item in a Q and A column:

Q. Dear Real Estate Adviser,
I have a contract to buy a new town home for $800,000, but recently I learned that since I signed, the builder has reduced the price of the same type of town home by $100,000.
A. ...As a general rule, values of new-construction multifamily housing -- including townhomes, condos and co-ops -- are a little more mercurial than single-family homes and can suffer losses faster than conventional homes when a market softens. But in the last few months, some single-family home builders have cut prices up to 25 percent in a few previously red-hot markets such as Las Vegas. These scenarios usually occur when speculators quit investing. Until recently, investors accounted for as many as one in four transactions in several of the hotter markets.