FWIW, a friend of my wife’s who is the postmaster of a small rural office said you don’t need a full loop, just an area that’s “all weather”, i.e. gravel, where they can turn around without backing up. Maybe you can widen the end of the drive with gravel on each side or something.
my house is on a hill.. any changes would require lots of work.
I just don’t see a reason to spend the money on a company that is simply being difficult.