You can offer whatever you like along with your listing to make it that much more attractive, but many things have little to do with Airbnb really, and it should follow best not count on looking at them if the guests breaks or abuses such amenities or features. Their liability is limited, understandably.
Needless to say, rentals that become too delicate or complicated tend to become quagmires.
@Rhonda335 Just mention that you have a car available on Turo and leave it at that. Don't mix the two, as it will get messy. Besides, the car won't always be available to coincide with your reservations.