Here's the tip: If he/she asks for a wire transfer, it's a scam. These days there's no one but scammers who are using Western Union for expensive equipment supplies.
I found a similar deal once. Someone actually got their listing onto Amazon, so I almost fell for it. They wanted $1000 even for a new/in/box Canon 70-200mm f2.8 IS II USM.
The Amazon fraud department got involved and informed me that there are scammers who do this a LOT with lenses. In most cases, they actually have ONE lens which they sell to ONE lucky recipient. However, twenty people paying $1000 (for the above-mentioned lens) results in a nice profit on a $2.5K lens, which they'll claim as having been lost in the mail or something. Sorry! =)