Okay cool maybe I'll even do intake fan on the far back right, and fan blowing out on the far back left?That should be enough, water based or oil based poly?
For the fan, one is enough, but you need to provide a place for the air you are blowing out to get in. Cross flow is best, so fan on one side and vent on the other, but in the side and out the back will work too. To dress up the inlet, find a grill or screen to cover the hole.
I used water based poly.