anyone know if there is a set fee to change airport drop off in the middle of the reservation? i have reservations for mia-fll at $436 for a convertible and the same car for mia-mia is 249$. Wondering if i can get the mia-mia reservation and then change in the middle to say i need to drop off at fll for a set fee that would be less then having the correct reservation. the prices are much higher for all car classes, id just like to get a convertible.