If you aren't using a glow fuel engine you might look at using acrylic hobby paints from the hobby store. Depending on your covering, and taste for the finished look you might try that. It is VERY cheap to go that way.you can use foam brushes to paint, and clear coat with cheap spray clears as swell. Some of the colors don't cover very opaque with one coat, but it ends up looking very realistic with a bit of a weathered look. You might want to try it on some scrap covering...
http://www.rcuniverse.com/forum/m_10.../anchor/tm.htm
A link to my finished pup, painted that way with intentional brush, and airbrush weathering...