I booked through Ryanair who allows payment without physical credit card. The booking was with another supplier who didn't allow me to get the car as when I arrived there their conditions were different to Ryanair's website . I had to cancel my booking and rented with Sixt. With them everything was easy, and their conditions matched with Ryanair's offer, accepting physical and online credit card, also Maestro debit card. I won't rent with any other company.