When I was looking in October, I hadn't bought hardware for the better part of a decade, and I saw all these older posts on forums for DDR4 at $1/GB, but the lowest I could find was at least $2/GB used. These days? HAH!
If I had a decent sales channel I might be speculating on DDR4/DDR5 RAM and holding it because I expect prices to climb even higher in the coming months.