Hey 30 cent, I don't know anything about the real estate group/ developers you mentioned (and i'm not too knowledgeable about that area), but it's not uncommon in places like Belle Plain(es?) to have an abundance of homes on the market. Really around the country it seems that many builders really didn't seem to be too worried about signs that the market was falling off and continued building at the pace of the huge building booms of the 90s/ early 00's. The one and only time I drove by Belle Plain, all I could see of that town (and as far as the eye could see) was little cookie cutter rooftops everywhere, it seems that developers really went crazy with massive new construction building in this town. I can't imagine that there was that much demand to live out in Belle Plain, it's quite a hike to the cities from there but I suppose there's already a fair amount of people living in the stretches around that area already so I might be wrong about that.
As the market dropped off, consequently you see a lot of half-finished developments and/or empty new houses/ apartments/ condos sitting around everywhere. I wouldn't find it surprising or worrisome (outside of a general market standpoint) that the housing values have dropped, this is pretty commonplace nowadays and builders especially I am sure are trying to recoup some of their losses and get whatever they can by slashing home prices. In regards to the quality of construction, I don't think there's too many new construction builders out there that are building quality-built homes so I wouldn't expect that anything built in a new development nowadays (except for very high end developments) is quality construction. As far as investing in / buying a home in belle plain, the question you have to ask yourself is if you anticipate values to again rise in that area and demand to live there to pick up again over the years...if so, now might be a good time to buy.
I don't think this post has been very helpful in answering any of your questions, but it's my two cents for what it's worth
