Dealing With Honest People...

I have dealt on eBay a bit and I always check out the sellers record
before I pay for the item.  What does one do when buying a mechanical
music box from a private seller and complete stranger to insure that
they are on the "up and up" and really intend to send the instrument?

I hate to sound so "hardened", but dealing over the Internet and
through email really does not tell you if the other person at the other
end is honest.  I am dealing with someone now on a music box and have
gotten no indication of any funny business but I really have no way of
guaranteeing I will get what I am paying for or if the other person
actually has the box -- anyone can email pictures whether they have
the music box or not.  Suggestions please!  Thanks.

Michael Pawelek