whatever you do...you have to have cool enough air for intake to cool room as you exhaust out the hot air...if you can stay in the 70's then you are set., but you will need a temp/humidity controller to turn on fans when temps/humidity get too high.

dehumidifiers workto pull humidity and I believe(just getting mine, finally) they will also help keep temps down,,,I understand them to work similar to AC... I'll let you know in a week or 2.
do some research on closed environments, and you will gain some more insight.

also, Zandor's show covered this I believe. peace