Dude build your own hut with 2x4's and double-layer panda plastic. Frame in a D/H and an A/C and you don't even need all that other exhaust crap. Temp and Humidity dialed in, Sealed room for 300 bux (if you buy a used DH).

You will definitely need some DH action in that room if you're running hydro.. a fan is not going to get your humidity low enough at night in that setup. Price aside, you're better off with a sturdy 2x4 frame that you design yourself with everything in mind (and can screw add-ons into later). Saving $1000+ is just a bonus.