Did you ask whether the car rental agency you are renting from offers pick up at the ferry dock in St. John to bring you to their office? Would certainly be a nice customer service plus at the end of traveling on planes, taxis, ferries with a group of 7 with kids and luggage. 🙂 If not, then yes most of the car rental agencies are just a block or two away from the ferry dock so not a long stretch to walk. There is a small park and a few restaurants near by if some of the group want to sit and wait while the designated drivers go and collect the rental.
Thank you for using VInow.com for your travel research. Have a great visit to St. John.