There are currently two threads in the "Painting and Airbrushing" forum on spray booths. Nothing wrong with asking here, but I'd recommend checking that forum also, as it is a frequent subject and always brings a lot of discussion.
I use a spray booth for rattle cans, but not for airbrushing. I airbrush at my regular modeling bench after moving stuff back from the edge. I always hand-hold what I am airbrushing, so I can turn the model instead of turning/tilting the airbrush at funny angles. With an airbrush I get very little overspray so don't really need the booth then. I crank down the flow so that overspray is not a problem. Cheaper too, since I use less paint.
I have made all my booths. Started out with several using a cardboard box with a piece of the cover cut out so I could lower a filter/blower combo into the top. Latest version uses particle board for box walls and sides, filter at rear, and a light on top shining down through a window.