I've been on the hunt for more shelving for my basement warehouse, in the past I was using pre-made wood frames from Menards and half sheets of OSB for the shelves - as cheap as I could go. Last spring I made two 8 foot sections this way for about $130. Just now priced out what that would cost today: $393!!!!! I'd bring it down to $321 if I cut down the OSB sheets myself.
Anyway, obviously not about to go that route. I found a guy on FBMarketplace who just moved into a bigger house with built-in shelving selling off "4-5 sets of shelving" for $100. From the picture I can see it's probably more or less nice stuff. So I went and bought it and spent the afternoon sorting it out. Most of it is 4 ft x 2 ft rivet shelving along with some 3' x 18" stuff, plus some cheaper metal tab assembly type. Came with 20 of the larger boards and 10 of the smaller ones, but there are frames enough for 30 of the larger shelves, which... this is a crazy amount of shelving to get for $100. He said he was surprised no one had bought it yet, he looked online and a three pack of these shelves is like $200, I replied, "well, I know that, that's why I'm here". Plus, my wife starts summer break today AND I filed my taxes.