Wow! You sure brought a full plate to the table!
1. Unexpected surprises wouldn't be called that; it we knew what they were.
It's really more about having the ability to adapt to the situation presented at the time. "Rolling with the punches": so to speak!
2, 3 & 4. If you can't be in the rig during a repair episode: there are lots of car rental agencies, and Motels across the Country. (Although I hope that you never have to put them to use!)
5. Why not just keep your Doctors as they are, and plan your trips accordingly? Hospital emergency rooms are meant for those "unexpected occurrences" that get all of us. Put them to good use. Prescriptions can always be mailed to you: find one of those mail forwarding services, and let them handle it...
I think that you may be trying to think too far ahead on some of these issues. Take them one step at a time, and the task will seem less daunting.