I had a similar email in response to some ads for my Dad's van.  They wanted
to send me a $5000.00 check, and after I sent them the difference between
the asking price ($1,800.00) and their 5K, their U.S. "Agent" would pick up
the van.

I emailed back to say that we'd had so much interest in the van that we had
to raise the price to 5K, and to go ahead and send the check.  Needless to
say, I'm still waiting.

Dave
'86 Westy