Thank you for your response.
I intend to write to Mr & Mrs Vendor and point out that the agreed amount has already been fully paid but I predict they will write back and disagree with what was originally agreed. Given that there is no written documentation on either side, what are the chances of it being accepted by the small claims court?
Would you advise to inform them during my response that if mediation is unsuccessful and they do bring a claim, I intend to bring a counter claim for the stock that was unsalable and unusable?
Would you advise doing a inventory of all the un-saleable stock in preparation for the mediator?