I think what the car spray boys do is to wet the garage floor to attract / hold the dust that gets kicked up by moving around. I've always had problems painting outside due to pollen, flies etc... I'm def no expert but would the paint finish not be improved by progressive higher grade wet and dry and then a polishing system? Rather than a complete repaint?
This guy is worth a watch. He's getting a good paint finish, with 50/50 thinning paint, sanding back, 60/40 paint, sanding back etc... polish and wax...
Why Build A Farr