The best set-up for a house band situation would probably just be a combo or something. I'v done gigs with my schools equipment and a valve-stave 65 watt is perfect. A PA system would be good but if you have a mixer and a loud Keyboard amp it isn't vital, anyway i think you should join a band as soon as you can, because when you are playing with other people you get better alot faster and it reflects on your own playing.

Anyway have fun that's what it's all about
Adrian