Once a year? not terrible. More, potentially bad. Car rentals are crazy expensive.

I took a week vacation with friends last year and it cost me more to rent a car to get to the location than the combined cost of every thing else. The car was only used to get there and get back, but it's not like I could only rent it for the start and end days.

Just having to rent a car a few times a year would kill most/any potential savings from an EV.