You know, your bid on eBay is supposed to be considered a contract and they tell you that before you place a bid but some people just don't get it.
Many years ago I listed a wheel on eBay. It was before the shipping rate tools that are available now so I included a link to Canada Post's parcel rate calculator, the dimensions and weight of the parcel and my postal code and said to verify the cost of shipping before bidding.
There was only 1 bidder and he got mad at me when I told him what it would cost for shipping. "How can you charge me $XX for shipping for something that only cost $x" and wouldn't accept that I had no control over postal rates.
I cancelled it just to shut him up and I never tried to sell a wheel on eBay again.