The minimum age of the renter or any additional driver must be 21. Drivers aged 21-24 may rent a vehicle by taking the collision damage waiver of $28.00 per day with liability remaining at highest level for the vehicle. Drivers over the age of 25 have the option of adding the collision damage waiver, which will reduce the liability.Additional drivers are charged at $5.50 AUDPer day, must present a valid drivers license.