Millbrae Cars typically requires a minimum age of twenty-one years for individuals wishing to rent a vehicle. However, it is important to note that some rental car companies may impose a surcharge for renters under the age of twenty-five, given that they are considered to be at a higher risk. Additionally, drivers may need to present a valid driver's license and a credit card in their name. Each rental agreement may have its specific requirements, so it is advisable to review the terms and conditions on the relevant web page for accurate information. For the most current details about their policies regarding age requirements for renting a car, checking Millbrae Cars' official website would provide the most reliable information.