I have my important server stuff duped via syncthing to an old external USB drive attached to my work macbook, which then has Backblaze Personal Backup running. That backs it all up with no storage limit for £70/year on their 2 year plan.

The only downside is if the drive isn’t connected for a few days, it checks it all again on reconnection.

I have about 4TB of files most of the time.

This way I have 3 copies of my files: 2 local, 1 remote.