A paint booth can be anything from a multi-thousand dollar set up to a $10 chunk of plastic stapled along your walls. To be honest, I don't have much of a booth at all. I have a 'big-honker' fan that moves the air out of my garage when I paint. It's a large squirrel cage fan from a big furnace. Without it being tacked down I'm afraid it would take off and fly around the room. It moves lots of air. You can see the paint dust disappearing into the fan and out the window. When I'm done there isn't much dust to be found in the garage. Sucks the fumes out as well.
I do it kinda backwards, too. I paint about 5 feet from the fan, which is pulling the air out of the garage and through a window. Most people do it the other way and have the fan pull air INTO the garage. Probably better that way, but so far I haven't had too much of a problem. My walls near my painting area are covered with plastic drop cloth, but other than that it's pretty much just a junky garage with a fan in the window.
But, if you've got access to a booth already, it might not be a bad idea to clean it up and use it. Keeps you from messing up your own place. A 3 sided booth probably works better than a garage, anyway.
Reminds me of the first car I ever helped paint. Back in the late 1960's, my buddy and I painted his 49 Ford with Allis Chalmers orange enamal...outside...in the dark...using a trouble light...in the summer. Paint went on real well, and we didn't have too much trouble sanding out all the bugs, either. Dang, there was a lot of them! Then he took his 22 rifle and shot a series of holes down the side to make it look like someone shot at him with a machine gun. Now I see that you can paint realistic looking bullet holes. Oh, well. The stuff you do when you're young! ;-)
Let us know what you come up with.
Andy aka Big Stinkie