I'll try to work round this way....
Price on ebay: 142.00£
They are VAT registered seller -20% VAT = 118£
Ebay wants a few pounds.... leaves say 115£ for seller
Courier wants 10£ for delivery.... 105£
Seller wants to make profit..... if he budgets any less than 10% he is an absolute i.... he also has overheads for storage, staff etc
So he buys tyres for far less than 25£ a pop....
Now going down futher to wholeseller, importer, customs, sea logistics, exporter in China, all the way to manufacturer... they all have overheads and want to make money.
So how much exactly do you think the company that makes these tyres in rural China spends on manufacturing one?
And would you want to put the resulting product on your car?