Has anyone mentioned the little compressor for painting fingernails? Someone I know tried it out and said it works. No regulator or moisture trap tho. Might be good for a starter compressor for painting single colors, ie not doing camouflage or other intricate work.
My first "compressor" was the spare tire from my mother's car! I pumped it up to about 60 PSI, which gave me maybe 15-20 minutes of use. I got a good workout back in those days, using a big foot operated pump that was borrowed from my dad's car. The tall Propel cans were about $6 back then, but when they hit $10, I went to the tire.
But the whole operation was really inconvenient, so when I entered college, I splurged and bought a Badger diaphram compressor. I got a combo regulator/moisture trap from Sears rather than buying expensive Badger equivalents. But it was a little noisy and didn't have a reservoir tank.
When I got out of college I could finally afford a silent compressor. I bought a second hand one from one of the guys running the LHS and got many year's service from it. It was so awesome to be able to quietly airbrush out in the patio at night, without annoying the neighbors. I often ran past midnight, and sound really travels in the wee hours.
When the compressor's head gasket and pressure switch failed, I moved up to a compressor with a larger reservoir tank (tThe Mako Shark), which is what I use today.
Now, all that being said, a friend who lives in a small apartment brought over a Spray Works airbrushing rig that had everything you would need. I think the only limitation was that it didn't have an automatic shut-off switch. But the system worked just fine and was very quiet. Maybe it would be unsuitable for large jobs, but for small ones like 1/72 planes it worked great.