I would probe further, but use an email address that you would not mind a scammer having. I recently picked up a TS-E 24 f/3.5L II in perfect condition and still under warranty for $1,300 (via craigslist). The seller was legit and trying to get some quick cash for a trip so the TS-E had to go. I nabbed it quick because that was a smoking deal. Your deal, if legit, is even better.