If you can grow outside you should be fine.For good results you need at least a 250 watt hps per 1 or 2 plants.You can veg under a lower watt flourecent,but to save hassle,i would just do what i did and get a duel spectrum bulb for your hps,means you can veg and flower with it.Just keep it twice the distance off your seedlings than you do when they are a bit more established.Water every 2 or 3 days or when the top oil is dried out.Get an ec meter to measure your nutes and run off ,alot of nute companies advise on a solution much too strong for cannabis.An e.c of 0.80-1 is fine.That is for soil by the way.I know nothing about hydro.As for ventilation ,not really important unless your running big wattage lights eg 600 or 1000 ,keep a fan blowing to circulate the air ,and if smell is an issue look into a carbon scrubber.
