There are several types of compressors.
In the Garage type, you have oil and oil-less.
The oil-less are not know for their longevity. If you even get a year or two of moderate use out of them, that would be a miracle. A guy who fills his tires up, and uses a finish nailer a couple of times a year would be the target consumer for oil-less.
The oil compressor, just like your car engine, has pistons and rings. You change the oil and it almost runs forever.
You use a trap to get any moisture/oil out of the air before it hits your hose.
If you are getting a bunch of oil in your trap, you need to install new rings.
The bigger the tank on your compressor, the better. This holds the air in reserve, so less noise and cycling from the motor.
An oil compressor with a 30gal+ tank is also big enough to spray Clear Coat.
=
There is also a compressor type that is made just for detail airbrushing :
http://www.harborfreight.com/1-6-hp-40-psi-oilless-airbrush-compressor-93657.html
These run all the time, are oil-less and would be used in a house environment.
They don't have the pressure, or the volume needed to clear coat a playfield.
-
So in an ideal world, you would buy a garage type oil compressor so that you could airbrush and clear coat your playfields.