I'm considering Restic and Backblaze B2 as my backup solution. I'm a little worried having read about the potential for unexpected restore costs. For example, I've read restoring lots of little files adds to the cost (reference). What are the things to look out for when backing up and restoring that can add to the cost? Are there any best practices to keep costs down?

For images, there is nightshade. For music, there is/will be whatever Benn Jordan is doing. For youtube, there is .ASS. But what about poisoning text on a web page? Is there any standard solution out there?

It should be relatively easy. I've been thinking about doing something myself, but figured someone else must have already done it.