Here’s a Netapp shelf with 24x6tb drives for $825. Your ongoing power cost would be high though. https://www.ebay.com/itm/126080434670?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=pMrWKqdCRAG&sssrc=4429486&ssuid=Cb1tGoNLT-C&var=&widget_ver=artemis&media=COPY
From what I can tell this is just the DS4246 expansion shelf. If it had controllers, there would be a lot more ports on the back. If I remember right, you can repurpose these shelves as a generic SAS jbod. I believe you need to reformat the drives before they will work with anything but a Netapp controller.