Conventional wisdom says anything goes up too much too soon eventually will come down. It will be ok as long as it comes down slowly and gradually. I don't know how big of a problem that 退房热 is in Shanghai. Actually the same thing happened in 1970s in Texas. Overnight many saving and loan companies found thousands of empty houses with keys on the doors. The owners skipped out of town for good! leaving saving & loan firms to hold the bag, ended up with bankruptcy.
