VENTISOL 20 Inch Shutter Exhaust Fan Wall Mounted, Aluminum with 1.65 Meters Power Cord Kit,High Speed 3500CFM, Ventilation fan for Garage,Greenhouse,Attic,Shed,ShopA 20" fan should be a lot of air flow. And for 200 bucks I think it's the optimum purchase. As long as it works right. Homerun.
this is the one i got