I've been thinking about taking this approach with a project I'm working on. Effectively, it'll give me a similar set-up to the garage where I painted my RV-6. Being married means the attached garage is no longer an appropriate location for spray painting... ;-)
My first step would be to use plastic or Tyvek to wrap the entire structure so bugs and random junk don't get in there.
Then I would cut a door sized opening in one end and build a frame where I would mount filters for incoming air.
Then I would cut smaller doors along the bottom of the other end and mount box fans there (3 worked fine for me, but more would be better).
I'd also put a big enough door on one end for personal ingress and egress and for the assemblies you're painting.
Mount fluorescent fixtures to provide adequate light, and clean all of the interior surfaces very well (the ceiling, wall, and floor), and you're ready to go.
Obviously, you'll need compressed air and <probably> a fresh air respirator, depending on the paint you'e using.
One thing to consider is that you need 4-5 feet of clearance around your project so you, the hoses, etc. don't bump into or drag something through the wet paint.
IMO, the big challenge with this arrangement will be lighting.
Someone will jump in soon enough about the necessity of explosion proof fans and lights. No need for that discussion again, it is all available via the search function.