If a seller is printing from the buyer's supplied address and the address is wrong (Undeliverable) the seller is not required to refund.
This is true whether the shipment is returned as Undeliverable/Refused or whether it is kept by the household it was delivered to
https://www.ebay.ca/help/policies/ebay-money-back-guarantee-policy/ebay-money-back-guarantee-policy?....
It's not clear what "fine print" you are referring to in a listing, but most sellers complain that it is too easy for a buyer to Dispute a purchase as Not As Described and get a refund, although there can be a question about who pays return shipping.
A seller can have a No Returns policy, but he cannot have a NO REFUNDS policy,
What was your experience? There may be a way to solve the problem.