Spark, living in boats around a business core is phase one of the Marinea Project, if you go to this page
and click on the pull down for phase one, you will see a picture that I took of the initial project's business center, a refabbed construction barge. Phase two will grow from there but phase one is the original "proof of concept" that will put seateading and ocean colonization on the map and in the history books.
Before taking it out to the project site, we'll have a new protective material applied to the bottom and landing platforms fixed to the sides for additional docking.
As for business, or a way to make money, there are so many of them, but farming will probably be one of the more popular methods. It really won't cost very much to live at sea, you can generate your own power and work from home.
Myself, I'll stay with robotic investing. It has been productive and stable so I feel comfortable letting my robots earn a living for me. Anyone can do that so there's one answer. TheSafeInvestor.com There are also annuities for those that prefer a fixed income.
Teaching is another occupation in demand. My degree is in mathematics so I naturally migrate to this type of back up idea but we will need welders, and boat repair people, can you teach that? I would think most any skill could be taught so that's another way to make money. You don't have to be board certified to teach, just to know what you are teaching. Divers will be very busy, learn to dive.
Rescue and other emergency services, professional gamblers, prostitution, restaurant services, small motor mechanics, and if that isn't enough to get you started, drop me an e-mail with what you like to do and we'll find a job for you.
Making money is easy, keeping some government's hands out our pockets is tough.