This is crazy, ok ... your property has skyrocketed in value. You suddenly are an asset millionaire but you can't afford your house. You like the fact that what used to be a run down neighbourhood with crime and poverty and cheap housing is now affluent. When you sell it, choose a house that was exactly like it was when you could afford it and you should be hunky dory with lotsa cash left over. It may suck a little, but the world keeps moving on, kids might step onto your lawn ... buy a rocking chair and a shotgun, this is America.