The problem is that Mastodon isn't really great for single-user instances (hassle to upgrade, slurps resources for breakfast, etc) but there are plenty of other ActivityPub-compatible software that is great for single-user usage, like Pleroma, Micro.blog, Akkoma and more.
[1]: https://du.nkel.dev/blog/2023-12-12_mastodon-docker-rootless...
I'm not trying to dissuade you from writing this - such guides are always appreciated by the community. It's just that I've seen a lot of inexperienced people try setting these things up with a guide and getting bit in the back a couple months later.
I think this underlines the impression I had that Mastodon software is quite bad in terms of server resources consumption, feels like a very heavy service to host. Probably lots of performance improvements are still achievable, and hopefully hosting it becomes cheaper over time.