everything you see or touch that hasn't been completely finished. go room by room, look at everything from ceiling to floor, turn clockwise so you don't miss anything. open doors, drawers, windows, etc, turn off and on switches. go slowly and carefully, looking for anything that draws your eye - scratches, paint drops, etc.

discuss each point with your contractor - make a decision which ones need to be fixed before you move in (for example, light switches not working), which ones can wait (a knob on back-order, for example), and which ones you can live with.