quickbud, with a 12x12 room, and you want it maxed, youll need a fare supply of $$$$$. youll need multiple hps, just get a ballast that can work with a converson bulb, so you dont have to get floros, or some MH. We need more info, like how many plants you want to grow, grow style, like flower small, or flower big? How much veg time, strains. List everything you want...