I listed an item as a buy-it-now with an interested buyer. I charged heavily on the shipping costs and a more than reasonable price on the item. I always ship overnight and with insurance through UPS. A different buyer decided to purchase the item through buy-it-now because the item was basically a steal, BUT didn't pay the shipping cost. I only received payment for the item, not the item plus shipping. I told them they needed to pay or else I had a different buyer, and then they left NEGATIVE feedback because they said that I wanted more than the BIN price!! Is there anything I can do?? I already opened a case with ebay, but the buyer cancelled it! Don't buyers have to pay the shipping costs?? TIA...I'm a new seller to ebay and it is not going so well!!