It really does depend upon your skills level and sight reading ability. If you want to accompany, there may not always be time to have an advance look at the piano part. You could play in Care Homes, where I have quite frankly encountered some very low standard pianists who get away with it because no one expects much in the first place.
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Keep these things in mind when selecting your location. The good news is that Kauai is small enough to reach almost any area of the island within an hour or so. If you find yourself in a rain shower one minute, it'll typically be sunny again just up the road. Ultimately, it's hard to pick a bad location on Kauai to stay for your vacation.