Spraying isn't hard. If you can use a can of spray paint, and make it look good and even, then you can spray a single stage paint. Single stage paint looks alright to me(beats the hell out of the yellow). A few buddies and I had the whole bus cleaned, stripped, masked, primed, and two coats of paint in one day. I'm not sure how long it would take to dry being rolled on, but with spraying it, it was darn near dry by the time we got around to the front(Climate will also play a factor).
I'm not sure if it'll work, but next time I do it I'm going to try and apply a couple coats of clear lacquer in order to hopefully prevent the oxidation. I'm not looking for show car finish, but I'd like some sort of protection from the oxidizing uv rays.