^^THIS.
dude listen: i was in the exact same boat as you a few years ago. dont bother, NA skylines arn't that great, they are WAAAAAY overpriced and you'll be pestered by the police.
Just buy something cheap to bomb around in for a few years, dont modify it (unless you HAVE to), save ya pennis then when you get off your P's. you can spend that 20 odd thousand on a tidy 34 GTT or 32/33 GTR