Legit question (and one that I need to answer for myself as well):
Would it be cheaper to keep the EV and rent a car for when you need to do longer trips? (also taking into account the additional hassle of renting a petrol/diesel car)
Only speaking for myself, I'd seriously consider renting a (combustion) car for an interstate driving holiday if it's a rare occurrence, like once a year or once every two years. It will become an exercise in accounting[0].
My silly-ish analogy is: I don't own a plane because I fly rarely enough that it's not worth buying a plane to allow me to fly wherever, whenever I want.
the short answer is that it depends.
I did the maths on my situation and it did not work out. It is currently cheaper to pay the $120 / month or so on insurance and maintenance for the second car as opposed to renting a car for the once a month that we actually use the second car.
The trouble is that renting a car is expensive and public transit is an even bigger hassle.
Chevy Volt. Perfect car. I can consistently squeeze about 60 miles electric city driving, and 400+ on a trip. Soooo disappointed GM canceled the program. No one ever understood how great this car was…