There are various brands of acrylic model paints including Testor, Tamiya, Polly Scale, and Accu-Flex and they are easy to use, and clean up afterwards. The other benefits are that they work well in an airbrush, they dry quickly, and stick well to most surfaces. The main downside with acrylic model paints is you need to be careful with traces of oil from your fingers or from lubricants as that can repel the paint. After all, oil and water don’t mix. To avoid this, properly clean your plastic model with water and detergent before applying the paint. A toothbrush can remove dust and oil from recessed detail areas.

Paint flow can also be a problem in some situations. The trick is to add a wetting agent to the acrylic paint when diluting it. Add a couple of drops of dish-wash detergent in a pint of water.