You betcha, KOHO can be used to rent cars! Though not all franchisees will accept pre-paid cards. Each franchisee may also be location dependant.
Just a heads up that for car rentals, hotels, and gas stations, merchants may put a pre-authorization hold (usually around 15-20%) on your card. This is by no means a charge, however, your funds will be held to the ensure you have enough to cover the purchase (plus incidentals where applicable). We can't release these holds ourselves. The correct amount will ‘settle’ within 10 business days after the purchase.
Hot Tip: to get around this hassle, book your rental car using a different credit card and then pay the final amount using your KOHO card. Happy Travels 🚘