As for my idea about the ventilation. Well here it goes.

Currently my plants are all crammed in a 15"x15" space. Because I moved to CFL's and they just don't light a WIDE area like the t12 tubes did (albeit not that well). I obviously have heat issues since this is in a closet and I can't get fresh air in unless I leave the doors open. Which I prefer not to do (I have pets).

So here's my idea. Go down to the local office supply shop and buy a box that is 18"x18"x18".

Cut out one side of the box big enough for a box fan, cut out another small part of the box on the other side for another smaller fan.

Flip the little box flappy things up top (I guess the opening). Straight up. Make this very rigid and strength it by joint them all together with tape. (plenty of it).

Slightly below one of the flaps. Cut with a box cutter in the shape of two backwards brackets. It should look like the following: ][. Kind of like a hinged door. This is so I can work in the area.

Line the entire inside with mylar. Plants will have to be watered outside the box to ensure the mylar stays clean and the box doesn't get wet.

Get a piece of plywood that is just slightly larger than the 18"x18" area of the box. Maybe 20"x20" or 22"x22". You get the point. Place it ontop of the flappy things that we taped up earlier.. This is for mounting my lights. Line the plywood with Mylar as well

All of this is so I can take it out of my closet and put it in my actual bedroom where it usually remain much cooler due to the central A/C ventilation, but yet it still gives me room to grow the plants 12-14" tall and still takes up a very small space. I imagine if I get a 2'x2' box I could comfortably grow 6-7 plants if I did LST (this is assuming I can get the most out of a 1 gallon pot/bag and only grew them to 1ft.).

I want to go HPS for flowering, but I'm having heat issues with CFL's and I'm really concerned now with going HPS.

What do you guys think of this grow box setup. It's pretty cheap to create since all it requires me to do is buy a cardboard box from an office supply store. Approximate cost not including the mylar or any of my existing setup: $3-4 for a good strong cardboard box.