And as people aren't saving them, they are going to be even more scarce.
There is a guy selling some on Ebay (he sold La La Land and now Guardians), but they're pretty hard to find. They are meant to be glued to walls, so once they're gone, that's it. There is no ungluing them
. I suspect that some of my sets, like Mad Max, are pretty unique. They were not sold on EBay and you had to know a guy to get them.
Also, even the people who put them up can't get them all. They work specific neighborhood, and not all neighborhood have the same posters.