Condos are the way to go but a lot of them require at least six nights stay. For a hotel you might want to try the Maui Beach Hotel. Their rooms go for ~$110/night IIRC. It's not great but it's not a flop house either and it's close to a pretty nice beach. I've never seen it crowded there.
That said, Kahului isn't where I'd want to stay if I came here on vacation but the place does have a pool and it's cheap by Maui standards.
Check here for condos...
http://www.mymauicondos.com/
If you stay someplace other than West Maui or Kihei (Wailea and Makena are OUT on your budget) you'll want to rent a car so you can drive to the good places. A three day car rental will probably run you $120 or so.
Golf at all? Try Pukalani. Nice course and I think you can get a round with a cart for under $70.