This cache is on private property with the owner's consent. Please only give this hunt 30 seconds or so and then ask the owner who will help you.
This cache is only accessible Monday - Saturday from 9 AM to 6 PM.
If you are on a cruise ship that stops in Opunohu Bay and come ashore, look for the FREE shuttle that will take you west towards Hauru Point. I think the driver's name is "Albert". If you are staying in the resort across street, it is a short walk.