static void Main(string[] args)
        {
            Car car = new Car("BMW", 5, "V8", 20);

            car.Display();

            MotorBike bike = new MotorBike("Honda", 3, "1000", 10);

            bike.Display();

            Rentalable rentableVehicle = new Rentalable(car);

            rentableVehicle.RentItem("Johnny");
            rentableVehicle.RentItem("Mary");

            rentableVehicle.Display();
        }