I actually have a VERY simple design for a paint booth. It is not professional but I have put a lot of thought into it. basically. what you are going to do is build a PVC cage wrapped in plastic. I recommend having a dual door entry. IE you will wrap the inner and outer compartments so you don't track dirt in. Use 3+ mil plastic drop cloth and plastic DUCT tape. Not the quack quack but heating and air tape. On the roof use 1 or 2 box fans to pull the air out be sure to NOT throw the plastic away as you will use that as a cover over the fans.
Now everyone laugh but my thought on this was A you are talking like 50-60 dollars worth of parts and B a clean environment as large as you may need.
