Difficulties hosting more than one service

I'm considering getting back to self-hosting again, but I remember a problem I never quite figured out.

My first services were a gemini server and lighttpd server and these were easy to set up, very satisfying and continue to work well for years. I also have FreshRSS and Calibre-web running well here.

But as I try to add more, sometimes instructions would include apache settings that clashed with the apache settings for something else. The instructions assume I don't already have apache installed and can just apply any settings I want.

Another issue, the new service might take over the domain, becoming the default service for the domain. I'm assuming that this is a port issue but I don't know.

Then there were docker containers. Some used docker compose while some did not.

One that I just couldn't get working was Nextcloud, which I wanted to host surveys from. They won't answer my support questions on their community hub unless I set up SSL though (which I don't plan on doing).

Does anyone have general advice on these issues? If it's just part of the difficulty of self-hosting, then maybe it's not for me. Too much time and energy was getting spent on it.

Thanks!