How many channels can you record at once? How much do you want to spend? I commonly use ten to twelve tracks. I have also gotten usable results in the past with three or for mics...
I usually Mic each drum (Kick, Snare, and Toms) and two more for overheads. Most of my projects run from 6 to 8 mics; the variance being the number of toms used. IMO, too many mics will make the mix mushy.