lol... it depends how many u wanna grow.... but u need the right equipment... sodium lights are best as they give off UV rays, but u need to keep a steady temp of about 37 degrees, also you can buy chemicals e.t.c that makes ur plants grow better.. also remember to trim off all the leaves on the bottom(the ones that will not end up turnin to buds) and make sure if u get any male seeds and it grows, you keep it far away from the females otherwise you will just end up with a bunch of seeds.

my mate averages at like 8 plants per crop, each plant gives him about 9 ounce

but hes on about getting a small warehouse somewhere and using that as a huge plantation