To clarify the normal tipping policy on charters. If you have a hired skipper onboard you tip based on the cost to hire him. You do not tip based on the cost of the boat. Usually you will pay 1000 to 1500 a week for a skipper. You tip based on that amount. It's also customary to provide meals. A hired skipper normally is just there to helm the boat. He does not cook or clean.
If however you are on a fully crewed charter the tip is normally based on the cost of the charter. In this case however the crew normally does everything while you are onboard. Just getting the boat provisioned and cleaned is a 2 day affair before you show up. They then basically cater to all your needs for the week. 10 to 20% of the cost of the charter is the norm which the Captain and cook divide. The crews are generally poorly paid by the owners of the boat so this is how they make their living.
George