grow room advice?

hey everyone. im currently growing in my apartment and all is goin well however im goin to be movin out in a couple of months with some buddies of mine. i would like to move up from my 250w hps to maybe a 600. i was wondering what kind of indoor grow rooms i should use. we'll be living in a house and they dont mind the growing and might try it themselves but we would like to keep it still kinda hidden so i figured and indoor grow closet would be best. any recommendations on size? light size? im looking to run maybe 4-6 plants but at decent size. thanks

Depends on the house really. Maybe one of you could live in the basement or take over a room downstairs and turn an upstairs bedroom into a grow room.

make a box 5ft x 3ft 5ftH

that gives u enough room to use the 600hps properly, and enough space on the side for fans etc...

theres no basement in the house. i was thinking in the garage or keep doing it in my closet. smell wasnt too bad the first time since it was in a small room. just put air fresheners and baking soda and whole bunch of shit. was gonna get a carbon filter for my grow tent though. would a 400 be better for heat reasons? im using soil now since it seems to be the lowest maintenance