For most painting, your compressor needs a regulator (which most smaller ones already have) and you need to turn down the pressure to 40 psi or less. With oil based paints, it's best to have a filter that will remove moisture, although I have painted without such a filter; just be sure to drain all the moisture from the compressor regularly. Some years back, 4 neighbors and I painted all 5 houses with 2 one quart paint spray guns. At that time I had a $30 Craftsman and one of the guys had a $50 Craftsman. We both had little 20 gallon compressors at the time. One gun worked as well as the other, but the more expensive gun sprayed a wider swath at a time, so it was faster. But, as I said, I'm now using a Campbell-Hausfeld paint gun (model DH3800) that cost me $19.87 plus tax at Walmart on Oct. 18, 2005. They last a long time IF you take them apart and clean them when you finish; otherwise a very short life. The friend with the $50 Craftsman years ago loaned it to another friend and when he got it back, it was beyond help because his buddy let the paint dry in it; only rinsed out the can.
Of course the pneumatic (or air pressure) paint guns are silent except for the hiss of the air flow that you'd get with an air blow gun and there's no vibration. When you get ready to start, get a big piece of cardboard and give it a quick shot or two to see what adjustment you might need on the air/paint/stain/air pressure flow and what the pattern will be. You need to be able to keep the gun aimed directly at whatever you're painting, the same distance from the target, start moving it before you pull the trigger, and release the trigger before you stop moving. In other words, you have to break or turn your wrist. It seems pretty simple but maybe it isn't. With the 4 friends mentioned above, two of us did the spraying, the other guy just could not get the hang of using the spray guns, so they did the paint mixing, refilling of the guns, moving the ladders, etc. These were brick veneer homes, but had siding on one side of the garage, high gables, facsia & soffits, and patio covers to paint. Four of us used latex paint and we went around a house twice in a day while the wives were preparing the picnic. We did one house a day, but the 5th guy wanted to use a Sherwin-Williams oil based paint, so we did one coat on a Saturday and the second coat the next day.
And those were in the days when we had a substantial amount of help from Adolph (Coors) and Bud (weiser).:laughing: