Water businesses are many. There are ample ways to make a living from the sea. People who earn their livelihood fishing, for example, often follow in the footsteps of ancestors or at least family going back a few generations. It is not exactly a modern enterprise, but rather an old learned art. It also takes a heavy investment in boats and gear. (You would want to inherit it all for sure.) Entrepreneurs who live on the coast can operate marinas, restaurants and inns, shops, and related boating services. Every type of business has its licensing and safety issues when it comes to existing on or near water. It can be a labor of love or a big lucrative industry.
Tourism is what I associate most with such activities. There are seasonal business and then those that exist profitably all year round. Alaska is certainly of the former type while Santa Barbara, California is one of the latter. I also think of Boston, Bermuda, the Bahamas and other resort islands. You can operate a circle line cruiser in Manhattan if you are city folk! No doubt if you are thinking along these lines, you have preferences. You don’t usually start from scratch. There is some kind of reasoning to your madness to begin a challenging new career.
Those who love to fish can start a deep sea company or work on a trawler. If you are a landlubber, you can work on a pier and sell t-shirts or rent out the best inflatable boats on the market to tourists who can afford to pay the premium to rent. You can open a bed and breakfast in a quaint cove or serve homemade chowder in a café. I have a friend who sells marine insurance which includes mega yachts. He meets a lot of very interesting people! Anyone who owns a boat needs his help and the business flourishes anywhere from the lake area in Michigan to Florida. It all depends upon your available capital and income expectations. You can just make hippie shell jewelry if you are so inclined. It is such an open-ended realm of possibilities. Artists in Carmel for a century have explored the sea in paintings and sculpture. They take advantage of the village atmosphere that attracts visitors from all over the world. The Oregon coast has its own draw right up to Vancouver.
First and foremost, you should assess the need for your enterprise and the local competition. Demographics will dictate ideas that work best in a given locale. You may elect to take on a partner and staff to avoid round-the-clock hours. If you have a spouse and children, consider their role. Financing is available from venture capitalists and banks. Writing up a good business plan that tells your story will be what is needed to sell your concept.
I probably have not included all the options here in regard to water-related businesses. Let your imagination roam as long as it stays practical and earthbound. I don’t care if you rent Jet skis or rafts. There has to be a need and the right time and place. Go big and start a coastal retreat, go small and whip up a hot dog stand. The ski is the limit, and the water, too!