Currently, the cheapest month to rent a car at Hakodate Airport is March. The most expensive time to rent a car is January. The cheapest prices for each month are shown above, but prices will vary based on availability, how far out you book your rental car, and of course, car type.
JR Rent a Car
JR Hokkaido Rent a Car
Yes, renting a vehicle at Hakodate Airport for a month is certainly possible.