Minaba. This company rents cars at 53,000 yen per month, including insurance. Competative with buying a car for a few months. They are used to custom from KEK ( mainly from SLAC, California) so they are patient and good natured if you speak fractured Japanese. The woman who looks after the renta-a-car operation is fluent in fractured English.

The cars may be a bit odd. They gave me a Rover ( made in UK ). Actually a British Honda.