My server runs Plex and has almost 50 TB of video on it. After looking at all the commercial backup options I gave up on backing up that part of the data. :-(

I do backup my personal data, which is less than a terrabyte at this point. I worked out an arrangement with a friend who also runs a server. We each have a drive in the other's server that we use for backup. Every night cron runs a simple rsync script to do an incremental backup of everything new to the other machine.

This approach cost nothing beyond getting the drives. And we will still have our data even if one of the servers is physically destroyed and unrecoverable.