First off, you're not gonna be able to milk 5-6 dry or undried pounds indoors unless you live in amsterdam. Also, a drip system would be the cheapest, to grow that many plants. If you want mass bud try a scrog with afghan or something, good growers can get 2 ounces or more off of 1 sqft of screen, for my first scrog I gor like .5 ouces per sqft. With afghans and a scrog you'ld prolly want 12'12' screen for that much bud but it looks too hard for a beginner.