Since Fannie Mae is part of goverment now,

They don't want to dump any of your property which caused goverment lost money. then buy this one at bargin price.

It is common these days some homeowner can't re-fi his house due to property value is under water. But they still can qualify to buy a small one. So they just use this way: Buy a small or cheap one first, then walk away with their underwater one. Thus, they still have their own house. Goverment just want to stop this practice.

Make sense?