At first I was sceptical aboubt SD, and not happy to have been forced into it. However, I have completely changed my opinion, prices are usually less than I  can charge if arranging myself, and problems which arise, like non delivery or damaged in transit are dealt with by Ebay, not by me. Even if a buyer messages with a query about delivery, it is picked up by Ebay and I am informed that I don't need to do anything. The only slight downside is that, as I have left all postage options open, Evri is the one I most often have to use, even though RM would be more convenient.