arilhasan said:Just received the sms from the buyer stated he felt that he is not treated fairly and the ribbon problem only hit below f4 at manual.
Did this happen to u when u were still using this lens? Did it also happen at the point of sale? And he only brought this up after 3 weeks?
If your conscience is clear that the lens is not faulty when you sold it to him, then be firm and say so to him. It may be true that the ribbon broke on its own, but that is the risk of buying 2nd hand, whereby an item has already been used, maybe even up to the point just below of failing.