When he gets there, just tell him you have to be somewhere by a certain time, like 30 minutes after he arrives. Thirty minutes is plenty of time to look at a vehicle, and decide if you want to buy it or not.
Good luck, let us know how it goes.
BTW - I am ging to move this to the general discussion forum, it really belongs over there ...Jeff
'73 swb 2wd
73-87.com