Ask for a copy of his contract, most employees don't even sign a contract as one is not presented at the time the employment commences. (Of course, most does not mean all). If they can't come up with a signed contract of employment that states "Employees are personally liable for any item they are loaned by the company for purposes of staff training" or other some such legalese, then I can't see how the manager can claim anything at all.

You should have gotten wheels running an offset of ET42 ideally for a vauxhall astra, if it's a mk3 you run 205 section tyres on a 17" rim, if it's a mk4 you run 215s but you can get away with 205's as the decrease in rolling radius is very small (1.34% to be exact if they are both 17" running a 40% profile). I work with aftermarket wheels and tyres and in this case it's very hard to say who is right - I've had people flat out refuse my advice then come back claiming I never gave it, but then I have also had people dutifully listen to my advice and go elsewhere to buy wheels that I simply cannot supply in that time period. Playing devil's advocate, if you have a mk3 astra I can't see any company selling wheels that are 7mm out of offset, as you would see it is incorrect straight away (lower offset numbers mean the wheel sits further 'out' of the arch, and vice versa) even if you agreed to having the arch lips rolled (which is an almost undetectable modification - it doesn't alter the appearance of the car in any way), you still couldn't comfortably hide a 7mm extension on offset. A mk4 can run ET38 wheels but without any passengers in the back or without any aftermarket lowering being carried out, but even so they are recommended to run between ET40 and ET42. I'm not saying I'm automatically siding with the supplier, as that is not what I'm doing - but for every dutiful listening customer I've ever had, I've had 10 more who have said "will that bolt onto my car, I don't care if it sticks out". If, as the email says - you have bought them on the strict recommendation that the car won't be used to carry passengers in the rear, and then done so - it is Caveat Emptor in my opinion. Buyer Beware... (Incidentally, any hatchback is a family car, just because it has five doors doesn't mean it's less likely to be modified with aftermarket parts and as such I think that argument is a non starter) With this one, you should write the cost of the tyres off, accept new rims and if debts are a problem sell them on eBay or something like that. It is possible that the court would accept your version of events, but it is also possible that the retailer could turn open their order books to show x amount of satisfied customers. The most sensible idea is to accept a new set rims. (Just to add, I have no bias here and I'm not related to the OP or the company involved in any way shape or form, this advice is given without prejudice and I am not a solicitor or law professional)