I'm in the same position myself at the moment dude. For me I think one exhaust 100-300cfm for my 400watt hps is fine and a can carbon filter.. Give the rvk100a's a look they come in kits for under $100 bucks with the blower, coal filter (and casing) and ducting. kinda simple Which will probably be best for us both..

Doing it yourself is apparently quite easy but I don't mind paying the bucks for a blower paired with the correct ducting and coal filter, ya know?

Oh and errrrrrrr I recommend hardboard, thats what im gonna use, but there is of course stuff like the budbox XL growtent, perfect for the serious grower not limited by budget.

Peace,
Denial