At what age should you have all your funeral expenses paid for if at all?
I don't know what your expenses will be, but I think at your age you should have it all set up / paid off.
For Jews, you should join a burial society if the congregation you belong to doesn't have automatic membership.
You want to buried with your people. My grandparents are buried in the same section as my grandmother's extended family, so when we go, we can daven at my mother's aunts and cousins as well as her parents.