You can do a good job with a rattle can but if you want a top job, I also recommend using 2-pack clear coat on top. Here I used 2 cans of USC SPRAYMAX 2K which is about $20 a can and duplicolor auto paint on a Benotto beater I did a couple years ago (and was promptly stolen) and the paint in the pics is dry, not wet.
But saying this, I've also done quite a few bikes and the cost of paint, stickers, sand paper etc came in at about $100 plus hours or labor so if you want a reliable job, I say go the powder coat route.