Hokay, if this is so, why is Lorton (yes the old prison town - lots of nice flattened land!) full of new McMansions and not townhouses, and PW full of upscale condos near transit to DC, and large houses out on old farmland, overbuilt and empty? It appears, at least from here that it's "Buy all the house you can't", and "Flip that House" that led to this, and the poor can't afford to do that. It's California and Florida with some of the worst housing crises, and they aren't low income housing states. Ohio and other Midwestern states also in a mess had economic problems outside of housing, so they got a double hit that brought them down?
It's the middle class playing upper class, and lower middle offered middle, and almost middle wanting lower middle, offered a deal that looked like a sure thing that led to this, and builders and landowners building bigger with more amenities, offered with an intrest only loan, isn't it? It's not the poor with no money to spare getting kicked out of their houses, it appears to be people with jobs - but not enough for the house they were sold, or they were laid off or bills got too high, or kicked by a huge increase they ran out of ARM?
If that policy for the poor to get housing was the reason, we'd have barely under 100K townhouses everywhere, I would think and not these big, over accessorised white elephants?