This is a hail Mary but... I'm still running FMP11 (.fp7) because it has continued to work for over a decade... but finally it's hitting the wall of Mac OS updates (upgraded to Mojave and noticed a bunch of glitchy stuff, was going to upgrade to Catalina, but know FMP11 won't work at all).

I don't use any web based part of FMP, it lives solely on my computer with simple layouts and manageable amount of records (no more than 2000) but I have dozens of databases that I use across different jobs that I really can't afford to lose access to.

Question is, which FMP should I upgrade to (I would rather not have to pay the monthly charge for 19 because I don't need all the bells and whistles) to at least try to keep up with the Mac OS updates?

TIA!

You can buy a single user license:  https://store.claris.com/individuals

 

If you want to keep up with macOS updates then get the most recent version of FMP.  As mentioned, you can buy a perpetual license and keep using it until it becomes incompatible with the OS again (keep in mind that with the current update cycle this could be sooner than what it used to be).