demi moore and bruce willis purchased the south tower penthouse at the san remo in 1990 , in addition to a maisonette on the lobby floor .
moore appears to have won the penthouse in the couple 's 2000 split .
she is now selling the 14-room penthouse at a $ 75million asking price , since she does n't spend much time at the home anymore .
if it sells at that price , it will break the record for most expensive upper west side co-op ever sold .
moore and willis were married for 13 years and share three daughters .