Yeah, I was really disappointed when I used one on my house. It kind of throws paint out rather than spraying it out. You would have massive amounts of orange peel to deal with.

I have a couple of the cheap HF gravity guns, and they are actually pretty good. A guy who earns a living spraying cars might not like them, but for the occasional hobbiest they are fine. I have rented stuff like pressure washers from those rental places, and know they have portable air compressors to rent. You won't need anything huge, I have painted cars and boats with one of those little 1.5 HP/ 20 gallon Sears compressors for years before I finally got a bigger unit, and while it was not perfect, it got the job done.

Good luck,

Don