^+1 There are many types of paint that you can use you'll just have to be sure to pick one that's made to be exposed to water or be sure to seal it properly with a good polyurethane or acrylic sealer. The most important part as Carlton said is to be sure that it has had ample time to cure and is no longer giving off any fumes whatsoever before moving your cham in to it. I usually will let my cage cure for at least a week or two outside so it can thoroughly cure and air out though if it's cold where you're at it could take much longer (the last one I built was during the winter and it took three to four weeks before it stopped giving off fumes). I used both stain and a couple of different types of paint on my custom enclosures. I used an outdoor spray paint from Lowe's that is for protecting wood patio furniture and then put a polyurethane coat over it and the stain that I used on the non-painted wood surfaces to seal it in. I also used rock textured spray paint for my faux rock background and used an acrylic multi-surface sealer that I also got at Lowe's. So far everything has held up great and there has been zero fading, runs in the paint, fumes, or any other signs of deterioration.
