I am usually in the ship area of the forum but came in here to check out tips on painting. I found that many of you are hoping to someday buy a spray booth, so I decided to share what I did a few years ago to solve that problem.
I had an old Radio Shack computer desk that measured 40" wide x 18" deep. I built a frame on it made of cheap 1x2 wood and built it up 24" tall from table top to top of frame. I covered the frame with 1/8th inch pressboard. I cut a hole in back, removed the back grill from a box fan and used those holes to mount it over the hole. On the inside back, I placed an a/c filter large enough to slightly overlap the hole. When the fan is turned on, it draws air into the box, thru the filter, and out the back. The materials, including the fan and filter, cost less than $30. I didn't buy a compressor. Instead, I bought an 11 gallon air tank, mounted a valve on it with 2 pressure gauges. This setup cost me less than $40. I had my system for less $70 and avoided having to spend hundreds. The first gauge is mounted before the valve and tells you how much air remains in the tank. The second gauge mounts after the valve. With your airbrush open, simply turn on the air valve slowly until the second gauge shows the pressure you desire. Close the airbrush, attach your paint well, and paint away. I did over 20 models before I had to refill the tank., which was done easily with the air hoses at a truck stop, and only used 2 a/c filters, which are cheap, and never had a drop of paint make it thru to the fan blades.
I don't have the spray booth anymore but am going to build another one real soon. Wal-mart has a nice student desk for just $22. I'm going to buy that for my table and put casters on it in the event that I want to put it against an open window, which is not necessary. One thing though, if you build one, use the fan on high speed if placed in an open window and on medium speed if not. If you use it on high speed without being in front of an open window, use 2 a/c filters instead of one to eliminate the odors in the room. You will not believe how great this works and it can be built easily in less than a day.
Hope this helps all of you who want to move up to air brushing and who, like me, can't afford to spend $200 to $400 for a decent size booth.