Grow Room set up, suggestions?

Hello,

I am trying to maximize my yield. I currently have a 5 x 5 closet about 8 feet tall. I have completely set up the room as follows:

Completely sanitized the room with antifungal, mildew, mold and spider sprays, wiped everything down clean and then coated the room in thick sheets of dark plastic to "black out" the room as well as keep anything from the outside from coming in. I currently have a 600w hps and a spare 150w hps. There unfortunatley is no way I can cut a hole through the wall to have an exhaust vent going out, however I do have a fan on and I keep the door cracked to help circulate air. Do I need an air conditioner to keep things cooler and help dehumidify the room? I am considering adding another 600w hps to help give the plants extra light. Thoughts? How many plants do you think I can fit in this set up?

Your are going to need exhaust simple as that. Plants require co2 and will suffocate if there isn't air exchange with the outside world

Also heat will build like crazy unless you exchange the hot air in with cold outside.