I say buy the M3 and stay with your parents, give yourlsef another year there then buy a house or Appt. also, if u think this way "Ill be driving fast and be cool for a year or two, then what? " You shouldnt buy the M3
get a cheap car.. thats IF you mean what you said, otherwise, M3 + stay at parents home for a yr is my choice, and u never know what the future got for u