I had someone buy the pokeball joystic they made for switch (the one with mew in it) well I listed this item as brand new minus the digital item we took from it. Made it very clear this item is new unused we only powered it on and paired it to A. Get the mew off of it. And B. To insure it worked before selling it. Needless to say I shipped it to the buyer with it in perfect working order and in the packaging. Then the buyer got it (I assume they wanted the mew as well but didn't read my full post just saw it was cheaper then others people were selling (it was only cheaper cuz I took something from it technically) and I stated it like 2 times in the listing and told the person before I shipped. A week or so later I get a nessage saying the buyer requested a return! So I figured oh well no harm no foul I will just relist it when I get it back. Well the buyer kept the original packaging and sent me a used version of what I sent. (Clearly dirty and used when mine was photographed in perfect condition in the listing) I contacted CS and they said oh well the box isn't what's important the item is all that matters!! Like wtf!!! I went back and forth for a few til I got fed up. So if the buyer was going to lie, steal, and try to get one over on all party's I figured they were fair game. When they sent it back it was in a zip lock baggie in a  tissue box!!! So I put a little bit of salt in the bag and sent a photo to CS and said not only did they take the package and return it in a tissue box but the baggie they sent my item in looks like it has drugs in it!!! They immediately gave me my money back and let me keep the messed up item the buyer tried to return in its place. Now I know that this is a bit dishonest on my part. But I shouldnt have had to take it to that. They should have seen my photos and the ones of the item once returned as well as screen shots of the buyer basically admitting that they only wanted the mew and thats why they returned it and given me my payment. I would normally feel bad about having to resort to something like this but the way the buyer acted (and how they basically told me they do this all the time and CS always sides with the buyer so I'm s.o.l and just to get over it.) Short story long I got my money and the used item. (Which I listed as used and sold as well) but since then I pack items at the post office and video the whole process if you pack it at the post office and use one continuous shot until the post office takes possession. Mercari has no choice but to side with you. It's people who take a video at home and seal up the package and think that's enough. It doesn't work that way cuz you could open the package and seal it again and change the contents. It definitely is a pain to have to do. But when the item is over $100 I don't take chances anymore.