Don't ever use Ebay return labels

I do my own work on my car to be frugal, and I've often bought parts from Ebay. I recently needed to return one (unopened) because I didn't need it.

Ebay (not the seller) offered a return label, but they wouldn't tell me how much it would cost to use, just that it "would likely be cheaper to use the label than to purchase shipping myself from the post office." I had to setup a billing agreement on my PayPal with Ebay that allowed them to pass along the cost of the label to me once the item was sent.

Yesterday, I got notified that Ebay had charged me $43 for using the label. The package was small (16x16x1) and less than 2 pounds. When I called Ebay the agent and her supervisor told me there was nothing they could do. They told me "mail is very expensive these days." Just wanted to warn everyone here...