Agree with vacationtime1. We bought snorkeling masks from amazon, the full mask kind. They pack easy. Don't even use fins, I look like an idiot trying to go backwards in the water. Use your park pass both islands really have cool national parks or monuments. We always buy most of our food and alcohol at costco. Panululu bakery in the big island is to die for and the bread makes very good French toast and sandwiches. I always bring a carryon that I feel with bread to bring back. Buy the Hawaii revealed book for both islands, you can get them on amazon.