public IActionResult Index()
        {
            var bookingVm = new BookingVm();

            var allCustomers    = _customerRepository.GetAllCustomers();
            var listOfCustomers = _customerRepository.AllCustomerList(allCustomers);

            var allCars    = _carRepository.GetAllCars().Where(x => x.Booked == false && x.ForRent == true);
            var listOfCars = _carRepository.AllCarList(allCars);

            bookingVm.AllCustomers = listOfCustomers;
            bookingVm.AllCars      = listOfCars;
            return(View(bookingVm));
        }