At some point I'll do a public writeup of my planned cost structure. Hetzner's EX62 servers (https://www.hetzner.com/dedicated-rootserver) are about 10 USD/mo/TB of disk and it would be hard to go over their bandwidth limits . Even allowing for RAID and/or multiple locations/servers for a file node, the cost is still low. The main advantage in terms of cost is the possibility of not spending money on outgoing bandwidth.