Sounds like he has quality mods, which is always a good start. Not China crap
Spraying always costs a bit, but since its just the body kit, shouldn't be more than $1k. If the paint is fine on the rest, don't worry about it, just get the kit done. Not too cluey on colours, but some colours cost more due to difficulty to match and/or metallic etc. Whole car will cost you minimum $2.5k if you have a friend who will do it for cash on the weekend or something. Probably more like $3-3.5k.
That power doesn't sound too much for a stock turbo at all. With those mods, he's probably uped the boost to about 12psi. That is fine with the stock turbo, but I wouldn't take it much further. It can handle more, but then you're starting to push it a bit hard.