If I remember well, a poster previously said that’s what he and his relatives did in the 1990s — walk away from mortgages and buy other houses at 1/3 off. Yes, it’s different this time. The numbers are larger so there’ll be even more incentives to let upside-down houses go back to the bank.

By the way, there’s nothing wrong (legally or ethically) with letting the lender foreclose. It’s one of the terms of mortgage contract and going into foreclosure is simply abiding by the terms of the agreement, nothing more, nothing less.