I backup to a external hard disk that I keep in a fireproof and water resistant safe at home. Each service has its own LVM volume which I snapshot and then backup the snapshots with borg, all into one repository. The backup is triggered by a udev rule so it happens automatically when I plug the drive in; the backup script uses ntfy.sh (running locally) to let me know when it is finished so I can put the drive back in the safe. I can share the script later, if anyone is interested.