It isn't fair however imagine if every buyer could return items knowing that the return postage would be paid for them?   Some would buy, try and return and it would become a nightmare.   So it has gone to the far extreme and now is pretty unfair for buyers.   Lets hope your seller refunds the return posatge and maybe you son should ask the seller to pay for the return postage. They can only say yes or no.

I get that, but this case is entirely different, they have various models they sell and they have sent me the wrong model, no fault at all of my sons, he did not change his mind so it is all their fault.  They should pay for everything.