Mobility-on-Demand (MoD) services can be enhanced through use of Autonomous Vehicles (AVs) to reduce manpower costs (among other benefits), and use of multiple classes of vehicles to expand service coverage and accessibility. This work presents a functional proof of concept MoD system accessible via mobile phone to utilize three classes of vehicles in combination: a road car, buggy, and mobility scooter. A common software architecture and primary sensor suite allows for flexible replication to additional vehicles regardless of vehicle model or even class type. Benefits of using these three classes in a combined service are discussed, and details are provided concerning the unique aspects of the conversion and systems integration for each vehicle. Various safety features are implemented to ensure safe user interaction with all AVs. The complete MoD system is tested in uncontrolled pedestrian environments as well as on road with real vehicular traffic.