If you have several “Cabins” that are used multiple time you should create a custom post type and then use a relationship field to associate them with boats. That way you can edit them once. I would also likely create an “Excursions” post type and then relate the boats to the excursions. But, this will become difficult to search, so it really depends on what you need to do with the information as much as it does with best practices.
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