If it sounds too good to be true, it's a scam.
First, pictures don't mean anything. He can go to google, type in Yorkie, and save a few pictures to his computer to pass off to others as his own.
Secondly, NEVER give your personal information out to anybody on the internet. You're setting yourself up for all kinds of potential problems doing that. Even small pieces of information (a name, a phone number, an address) can be used to find much more information about you if the person knows where to look.