We give you the option to pay for extra seats to meet the minimum if there aren't enough people signed up for the public sail. If you choose to pay for the extra seats in order to meet the minimum on the public sail and have the boat to yourself, a minimum gratuity(20%)of your total ticket price will be added that is payable before departure. If your group meets the minimum number of seats needed for departure and your group are the only passengers on board (you have the boat to yourself) a minimum gratuity(20%)of the total ticket price will be added that is payable before departure. If you are booking for 8 or more seats on a PUBLIC SAIL, advance TOTAL payment in CASH is required. A 20% gratuity of the total ticket prices will be added to your cost. This gratuity is payable in cash only before departure.