What type of fan should i use??

I have a cfl grow going right now but i have a huge heat problem and that is all that is holding me back. got a 5 chamber cab lined with mylar. I only have 2 of the chambers working now and i would like to get all 5 up and running soon but i need a fan that will keep my cab at a good temp with the doors closed and the cab sealed. I have my top right chamber vegging and my bottom right flowering but because i have to keep the door cracked with a fan on it i worry about light penetrating my flowering chamber so i seal it off with some towels when the lights are off. I have to wake up everyday at 8am (way way way earlier than i should ever be waking up at this stage in my life) to take the towels odd but got drunk the other night and didnt wake up until like 10 and raced to find that it was incredibly hot (said 99*F but im sure it was higher) but the plants are ok. I was looking at comp fans when i realized that those were not nearly enough and was thinking of an inline duct fan of some sorts but could use some help finding something affordible that will keep my cab at a good temp so i can leave my apartment for a night and not worry. fan would be on the top with vents at the bottom. any help would be awesome. thanks.

pics here are of the full cab with the 4 veg/flowering chambers and the cloning chamber at the top. other pic is one chamber with the 6 lights. planning on the other 3 chambers being about the same with the same amount of lights if possible.