that is ridiculous of them. How much was it? When you open the case in ebay, if you tick the box marked 'other' then type in next to it 'refund' you should get an ebay no fault refund of all of your money without the cost of returning the item. Then you can leave appropriate feedback and stars.
It was 20 pounds for a kids' cd-player, which would have been over 50 pounds new. Thought it was a good price at the time. Well.. it would have been. Also the radio aerial was snapped right off and not in the packaging, so would have been broken already when sent (and not mentioned in description).. Rubbish!