I am writing here to get information from people living in Canada on what would be the best option to have a car for six months, without it being too expensive?

My brother has the ability to work remotely for his job at a French company (which has no connection to Canada) and has plenty of holiday “credits” (about 80 days) to use before the end of the year . His plan would be to spend 6 to 8 months between Canada and the United States, starting with the region around Calgary. He would like to spend about a month in town, working part-time (2 weeks off, 2 weeks on), but being able to enjoy the neighborhood in the evenings and on weekends during the weeks he works. Then he would take another few weeks off to roadtrip to another place where he would spend another month working, etc.

We first considered renting a car, but the price skyrocketed compared to car rental prices in 2017 (for our US roadtrip).
We looked at peer-to-peer rentals, on sites like Turo, but it seems just as expensive.
We were thinking of buying one and then reselling it on leaving. The big question is that of insurance because we have not (yet) been able to find insurance that would agree to cover a “long-term” tourist. Obviously, the insurance should cover both Canada and the United States. If you know of any, I’m all ears!

How about finding someone who has a car they don’t use and would be willing to rent it privately (much like Turo), obviously with us also paying part of the insurance? Do you think it’s possible?
Any other idea on how we could do this? The car is really the big question mark of this trip.