They usually give you a half hour. We are always over that. Our driver has never charged us extra or made any comment about being an extra 10-15 minutes. Instead, we give him an extra $5-10 in his tip. As far as times to get POR, it should only be 15-20 from the grocery stop. We go to the Publix in Williamsburg and it is roughly 20 minutes to get to Old Key West. Hope this helps you out!! Have a great weekend.