eBay

If I sign up and become an eBay store is it mandatory to take returns and is it mandatory that has to ship within the first day?

Went to the post office and 4 out of 7 would not work to print label 

I listed a item and did not promote it. I sold said item in one day and was charged 13.5 percent plus .30 for a total of $6.12on a $30.00 item. Why so high? What does variable percentage rate mean? How does it vary? Why am I paying the same rate if n...