that's a good attitude to go into it with.

budget an extra 50% for incidentals and have at it.

there have been a few spray painting threads before. some of it is good info. again, i think the key is light coats. you should barely be able to tell the difference after a coat (kind of) if you aren't accustomed to it. follow the directions for whatever paint you're using and paint in dry, 70 degree weather.

and don't be afraid to do crazy stuff, beyond just getting sparkles in the top coat or whatever. some of the coolest bikes i've seen have been sharpied or paint splattered.