We painted one of our boats with a brand of paint called Jones Blair. They use this paint a lot in chemical plants and it takes a while to dry but is very very hard, and scratch resistant. They make it in many colors and we have even used their clear over ppg paint. One time the nose of a fountain went up on the side of our bow while docking. He ran it up there pretty good and that is two edges rubbing eachother. His jellcoat was trashed and we just buffed some scratches out. The only problem is the lengh of dry time. It takes atleast a day out in the blistering sun.
Don't worry about painting in a not so paintbooth like environment. We painted this is a dirt floor barn. just washed the spider webs down and wetted the floor.