Best FB Groups for Buying/Selling GU Items?

[GoCrazyFolks76]

I'm just wondering if anybody here has experience buying and selling items on any of the Facebook groups.

If so, which ones would you recommend.

Thanks!

[metman80]

the main one is MLB Game Used

the majority of the posts are people showing off their collections, but some selling can get done if the player is popular enough. I have not moved a single Mets item there since I joined, which was at the very begging.

I have my own separate Mets one as well, as many teams do as setup by fans