[quote name='bassman7755' timestamp='1478006776' post='3165905']
In the event you do agree to pay towards some work then make it clear you will only pay the repairer directly.
[/quote]
[quote name='stingrayPete1977' timestamp='1478006828' post='3165906']
And a copy of the receipt plus the luthier's number to give them a call, then I would tell them to FO anyway
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I would advise very strongly that you do NOT do this, in fact that you do and say absolutely nothing that might imply that you felt any responsibility or liability at all.
If this guy really is a scammer (for £230? sounds more like a newbie or an incompetent to me) then he'll know how to parlay your tacit admission into complete liability.
Just say, as politely as you think appropriate, that there was nothing wrong with the bass when he bought it, and it sounds as if he's been scammed by a dodgy luthier.
Ball --> his court.