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datahoarder
Who are we?
We are digital librarians. Among us are represented the various reasons to keep data -- legal requirements, competitive requirements, uncertainty of permanence of cloud services, distaste for transmitting your data externally (e.g. government or corporate espionage), cultural and familial archivists, internet collapse preppers, and people who do it themselves so they're sure it's done right. Everyone has their reasons for curating the data they have decided to keep (either forever or For A Damn Long Time). Along the way we have sought out like-minded individuals to exchange strategies, war stories, and cautionary tales of failures.
We are one. We are legion. And we're trying really hard not to forget.
-- 5-4-3-2-1-bang from this thread
Ahh that makes sense. In that case I think AWS Glacier might be your cheapest option. (At least until you need to restore).
Edit. That said a safety deposit box might still be an option if you vacation or visit a far away place somewhat regularly. Just update it every year or so. Keep changes waiting to be updated in a cloud backup. This way your not backing up and paying for 30 TB in the cloud but maybe 1-3TB of recent data that hasn't been backup to the safety deposit box. That cloud backup size would get reset once you successfully update the safety deposit backups.
I am not sure what the best option is software wise for actually accomplishing this world be. But something to think about.