I made one on the cheap with a bathroom fan and a foam type filter, so it doesn't clog and reduces the re-circulation of paint, set in a 5 sided, clear plastic box. The main idea was to minimise spray drift around the room from coating everything. I don't use toxic paint but you should still wear at least a dust mask with a spray booth, if not some more serious RPE, 'cause any particulates getting in your lungs isn't gonna do you much good.