[zedrox464]

I just need to box the return after I receive "replacement"

Okay, so the SE Is an AR.

Given the Item's value and as per your Intention below, they'll most likely check the return.

and send them an old busted up laptop I've been meaning to throw away

If you've used your very own payment system for the original purchase, they'll debit your account.
How do you plan to circumvent this?

The laptop was bought on amazon according to the ebay listing and I got all the info required from that listing. When doing the ar, they somehow did not ask for any payment details. If they did, I had a $10 privacy card generated just in case.