if he actually does it--probably wont, but if he does--tell him since he's provided proof of vet check for the puppy--someone else interested in purchasing one too and you want that vet check as well...maybe you can get him to nickel and dime his money away---he'll be loosing more and more money everyday
And as a last resort--can always tell him to go buy today's news paper with today's date....place the puppy on the newspaper with the date within view and snap a picture......then email that to you as well.