So close, and yet so far.
If the house has been condemned as uninhabitable, then the city can force the occupants to leave until the structure is repaired. It's not a short process, though, and if the occupants can't make the repairs or find another place to live then it could drag on forever.
But really, Jay, you shouldn't have been destroying their house bit by bit just to get rid of them. If anything your efforts have only made them stick around longer. Next time try damage that isn't likely to get the house condemned.
Also, you jinxed yourself by celebrating before closing.