One or two plants.I would go with the DWC buckets.Low cost and you can DIY them yourself.One air pump and a coulpe air stones.You can start out with CFL's and switch to HPS in flowering.DWC grows some nice big plants too.Are your room mates willing to take the change of being BUSTED if the law comes to your place?LOSE LIPS SINKS SHIPS.Two many poeple knowing what you are doing is bad.Or one of them getting piss off at you and you will be staying at the iron bar apts.Just my opinion.PEACE