You don't need nearly that much. 26TB factory recertified Exos drives are $360 a piece on Amazon and a 4-bay UGREEN NAS is under $500, so you can do 100TB for under $2000.
More compute, redundancy etc. of course adds cost but even with RAID1, brand new WD Red drives and a PC build, you should be able to do under $6000.
I spent $2550 on a TrueNAS setup with 3x22TB drives, so 40 TB usable after setting up ZFS. The case can hold 8 drives so I could go up to 120TB usable for an additional $2000 at $400/drive. Building big storage servers is actually much cheaper than you think nowadays.
The rest is gravy.