I've been using Syncthing to sync my notes... it doesn't work on my iPad (because of the way the iPad file permissions work) but I'm able to sync between my phone and my personal computer and work computer. (I also have Syncthing running on my NAS so it's automatically backed up!!)
Syncthing doesn't cost anything. You could also use dropbox or google drive or whatever so you don't have to pay. I agree, it's a pretty steep fee for what it is.
So I have a folder called people/ that contains a note per person that I work with. (I have a template that helps create what I'm about to describe for each person too so creating one of these people notes is as simple as typing their name). In there I have what you'd expect, name, email, position along with maybe some personal notes I want to remember about them but then I have a dataview table that lists all the meetings I've had with them since I started taking notes.
To do this, it's a simple dataview table in the person note and then I also have a meetings/ folder where I add my meetings. In there, I just have an attendee's section where I put people's names (just using the [[name]] notation) and obsidian links them and the meeting will show up in the table.
I can also add todo items right in this meeting template and using the tasks plugin, I can create a list of tasks that it pulls in from all my other notes. So I have a daily journal note and this has a list of all my uncompleted tasks. (Again, all this is templated so I just have to open today's journal entry to see these things)
And to top it all off, it's all in just plain text markdown files so I'm not locked into some proprietary format.
I currently use Syncthing and it works with the exception of syncing to my iPad (and I imagine iPhone but I have an Android)... need to figure out something else for that. I did see someone somewhere mention CouchDB combined with https://github.com/vrtmrz/obsidian-livesync so I might try that and see if it works.
It's probably not a static-ip and I wouldn't rely on it as such. I'd use http://www.duckdns.org/ to handle the dynamic IP issue (or something else, https://freedns.afraid.org/ would be another option)
I'd look to pihole to start with for DNS. It blocks ads and you can add manual DNS entries. If you need something more complex, you can always migrate to something like unbound but pihole is a good, easy start.
Setup https://letsencrypt.org/ You didn't mention HTTPS/SSL, but you should really set it up. let's encrypt makes it easy and free
I've been using Syncthing to sync my notes... it doesn't work on my iPad (because of the way the iPad file permissions work) but I'm able to sync between my phone and my personal computer and work computer. (I also have Syncthing running on my NAS so it's automatically backed up!!)
Syncthing doesn't cost anything. You could also use dropbox or google drive or whatever so you don't have to pay. I agree, it's a pretty steep fee for what it is.