I have better equipment now but I started with a cheap touch up gun from harbor freight and a roll around compressor. It has gotten me by for years. Harbor freight has a HPLV gun which when it on sale is quite cheap. I have painted a lot of things wth that and it has done fine. Do add the disposable filters though. As the compressor warms ithe air will creat moisture. It really is not an issue with cowlings and small things but it is a bigger issue when paintting a lot more volume (such as a car).

I am not going to kid you though, it is expensive. I typically use Centari (Dupont) which requires a catalist and thinner. It does add up pretty quickly. Pick a color you can paint other things with which helps defer some of the cost. The first time you paint with automotive paint you'll wonder why you ever picked up a can. It dries hard so you can handle it the next day which is nice too.

On the flip side, many people I know swear by rustoleum. It may be an alternative. If you chose to go with Centari, let me know I'll help you as much as I can.

Gary