If an item doesn't sell on
ebay, there is no final value fee. However, you paid a listing fee upfront (I think it is approximately US$0.30 or so for 7-day auctions and US$0.20 for 30-days in
ebay Stores). YMMV in the U.K.
For items that may or may not sell, the Stores listing gives a much better bang for the buck, as it can be configured to auto-renew.
However, if you have a large inventory with little turnover this can get VERY expensive. For most small- and mid-sized sellers, this (and the previous) "fee reduction" (as marketed by
ebay) actually raised up-front fees, which is a double whammy to many sellers. Not only did the fees go up, but it's at the front-end on everything listed, not just in the event something sells.
I have been slowly decreasing my
ebay listings (my
ebay sales a primarily NOT stamps... mostly coins, CDs, and random and sundry "stuff"), and have been exploring other venues, e.g., BidStart, but the sad fact is that no other venues produce the same results as
ebay. It's the 800-lb gorilla in the room.