My advice would be to buy an oiled compressor versus an oil less one, but most compact and home owner units are oil less. However, the comments about getting a very good filter/water separator are something you need to pay attention to! Air compressors (oil less in particular) tend to pull a significant amount of water out of the air, and it can and probably will be picked up when you least want it i.e. in the middle of the 2nd or third coat of a paint run.
l ruined a couple of good paint jobs when water in the air stream splattered on the piece. /DesktopModules/NTForums/themes/mls/emoticons/sad.gifI also ruined the nozzle assembly of my plasma cutter with internal rust when I ran it with out a dryer/filter and then just put it up./DesktopModules/NTForums/themes/mls/emoticons/crying.gif
The replacement parts were about $400 for my lesson in the dynamics of compressed gasses and I bought a replaceable dryer filter for about $100. Hard lesson learned....../DesktopModules/NTForums/themes/mls/emoticons/blush.gif
Another thing you will want to do is drain the water out of the tank periodically if not every time used to keep build up and rusting to a minimum.
You additionally may want to make up oiler type line to insert when using nailers and other air tools like drills, shears etc., to help lubricate those tools. I now use a 60 gallon vertical 5 hp oil filled unit instead of a compact oil less, with an in line 4"diameter oil/water separator and still utilize a dryer and oil filter when painting or using the plasma cutter, and I drain my tank weekly since it's pressured all the time./DesktopModules/NTForums/themes/mls/emoticons/whistling.gif