If the car was stolen and the insurance company paid out before it was recovered then they would of given the policyholder the chance to buy it back. If they decided not to then the insurance company would of sold the car on to a salvage company, generally for a big loss.
You have the potential for a good deal here, but. I would arrange for the meeting to be in a public place or at the sellers business premises (if its not a business walk away). They should have the salvage receipt and documentation from the insurance company including the V5 and all supporting documentation for the car, the insurance co would of insisted on this from the policyholder.
Get the car checked over from the AA, confirm its history with HPI and also call the selling insurance company and confirm they sold the salvage to this company. If its all green you will get yourself a cheap car.
