any compressor with a tank will do the job, the smaller the tank the more often it will refill, the larger tanks have larger motors which generally means more noise.
it will depend on your situation as to how much noise you want to subject your neighbours to and your hearing can cope with. if you like to paint in the wee small hours then maybe a 'studio' type compressor is what you need.
definitely have water traps on both the compressor and the brush, I run a small 'studio' compressor, and just recently its had water in the trap, but its been hot and humid here