eBay

the seller have to cancel the order or can they refuse to cancel?

I sold an item to a seller and have agreed to send them a shipping label for them to return it to me. How do I do that?

I am a seller. When I sell an item and charge shipping, am I paying fees on the shipping charges? Would it be cheaper to increase the price of the item and ship it for free so I can count the whole shipping cost off when I file my taxes? Thanks