I am 62 years old, not significantly overweight, but was never blessed with Conan-like physical characteristics. I have had the front wheels off my Ford E350 chassis motor home just this past summer to change the front springs to softer-rated ones. I am happy to report that I can handle a wheel by myself with no concerns.
A 6-ton bottle jack and tire iron are the two basic items required to lift any corner. A higher-rated bottle jack will be much heavier and much harder to handle so I don't recommend the over-kill.
Our spare tire is stored chest high and I am able to get it up and down myself, but I can see that my days are numbered in that regard. I can see resorting to a camping neighbor one day if I ever had a flat to deal with.
I maintain the full 80psi in the spare tire, then plan to let out the right amount of air pending the location it is mounted.