My suggestion is to let the seller know a day or 2 before you are going to look at it, that you want the bike to be stone cold when you arrive. Feel the pipes to make sure it is indeed cold, then ask him to start it for you. Stand behind smell the exhaust and look for oil smoke for maybe 30 seconds or so, then stand next to it, see if there are any weird noises, then take it for a spin.
