| I'll second DJ's valuation, BUT never underestimate the cost of repairing bikes and getting them back on the road.
There's frequently other things damaged that you don't spot that add to the bill so i'd err on the side of caution.
Even when rebuilt depends on service history and number of owners. Its easy to track down an owner on the island and check the history if someone is buying it from you.
Difficult to value damaged bikes unseen but i wouldn't offer more than £2500 absolute tops and preferably £2000.
Why isn't the owner repairing it himself if he hasn't made a claim, or has he made a claim and it's written off?
Isle of Man is still part of UK and surely will be insured by a mainland insurance company so could be on the register.
Sorry to sound cautious but unless you've seen it or know/trust the seller i'd tread carefull.
Good luck | 
Hybrid Mode
