think most electrics are pretty similar in ease of use. no idea on diesels.
depends how much money u have, what u wanna spray, where u wanna use it, 3 phase 240 or 110 etc
u can hire them from ces hire, and i think 1 of 2 other places. think hiring might be asking for trouble if u dont no how to use em incase u damage it.
where abouts u based? might be worth askig some1 local with a machine to do a day with u and show u wots wot