This guy I work with want me to buy his 89 Rex So. It's had a professionally done b16a swap, has hotlink shocks, decent springs, lightweight wheels, corner weighted setup, and a fresh paint job. He bought it new and never daily drove it. He's meticulous about everything, and I trust that he took care of it. He doesn't expect more than 4000. Should I just write him a check for it and not think twice, or should I haggle?