Make sure you check your monthly invoice very carefully. Mistakes can and do happen, but when I noticed I was being charged a $60 service fee on an item that only made $156.50 the red flags started waving mightily. All it took was a phone call to the very helpful eBay person to put it right, but................
eBay is a very useful medium to get rid of 'stuff' that might be unsellable otherwise, and I enjoy using it, but.....