Yes, you pay postage. If you have a local Disneystore, you can do returns there of most items.
IF an item arrived broken, try calling them. (google the phone number, its hard to find) They sometimes send a replacement and don't require you to return it.
I put it back in the package it arrived in and stood in line at the ups store for about twenty minutes. It was 19something for ups ground and 20something for uspost. I'm irritated because if I had any idea it would be that much I would have gotten a priority mail box and done it that way. It had already taken so long in the store and there were a bunch of people behind me and I was irritated with my kids. Annoyed that I wasted so much money on shipping a return. Lesson learned I guess.