Had that happen two weeks ago. Seller messaged me after the package shipped asking me to rate so he could "get paid". Suspicion #1. When the packaage arrived the following week, it had a jumble of mailing labels and my address was in a folded over part that was really hard to locate. Suspicion #2. Bust out the camera before opening. It ended up being a loose car part to a Buick instead of the Coleco handheld Frogger that had been ordered...

I'm feeling like the whole thing was an attempted and failed scam. I contacted Mercari with the photos. They had me ship it back. As soon as I confirmed I shipped it, the seller posted the SAME photos listing it again.

Seller confirmed receipt 2 days after it showed delivered. Finally got my money back.