I don't see a problem ending an item early on ebay, if you agree a local deal with a buyer off ebay, why not save the fees and split the saving between you. If another buyer misses out because of this, frankly if they really wanted the item they should have approached the seller in the same manor. I think ebay fees are well over the top, so why not treat it as a virtually free (excluding listing fees) advertisement and if the opportunity to do a deal off ebay presents itself, go for it.