Before you do anything it is good to get a phone number at their place
of business along with the main business number of his place of
business. Then, call the place of business and verify his
position and title. VPs, CEOs, etc are all believable owners of
5970s; guys at the bottom of the food chain are less likely (unless
they got in early and have lots of options).
I don't have any experience selling, but if I were to sell, I'd go to
the bank where the buyer got his cashier's check and ask the bank to
verify that they issued it. Then, I'd exchange it in
person. When we're talking about something that expensive, there
is no excuse not to do the transaction in person.
Eric von Schonberg