Our group (6 adults, 3 babies) have arranged for a private shuttle to and from the port. On the way TO the port, we will be stopping for 30 minutes or so at the Walmart to pick up supplies. On the return trip, they will be bringing us to the airport to drop off 3 people, then the rest of us will be continuing on to POP Music. Just not sure what appropriate tip amounts are for each way. Our transport is $280 round trip.