@MicheleandLouw0 - While you can create a listing that includes a "car", Airbnb will not cover you in any way for it should the guest damage the vehicle in some way. You will be on the hook for any physical injury that they may endure should they get in an accident (including any injury to anyone else). If the guest should steal it, Airbnb is not going to cover you with their Host Guarantee. Your insurance company probably won't cover you either, so you should check before doing this.
My suggestion would be to find the best possible low-cost options that guests can take advantage of while they are staying with you and let them find their own transportation. You have Uber, Hello Cab, and car rental agencies (Avis, Hertz, Bidvest, Europcar) that guests can use. Or send them to CarRentals.com from Expedia. This just sounds like a bad idea and one where some unscrupulous guest will sue you for everything you own because they get in a fender-bender. Please make sure you talk to a lawyer before you start renting a car to total strangers who book a room with you.