It's been probably 5 years ago, but I bought a ceramic (Disney) item from an Ebay seller. It arrived in pieces. And truthfully it was not packed well.
As soon as I opened the box I saw the damage and just took it to my local USPS store.
They said it was packaged well enough. (I did not think so, but I certainly was not going to press the issue!)

I had to fill out a claim.
In turn that was mailed to the seller.
I had contacted them already, and luckily they were very nice. It was up to them to sign over the damage claim so I could get reimbursed for what I bought. They could have been a real stinker and let the paperwork sit and I am not sure I could have had much recourse, if any.
I received a refund immediately once the paperwork was returned.
I don't recall how I was contacted the refund was ready. It seems the clerk at the local store issued me a money order, which I promptly cashed there.
I was lucky that it went smooth. The postal clerk and seller both were on top of it.