Someone I know well wanted to sail around the world. Learned to sail, and she got to know people with boats who needed crew to take shifts on their sailboards, and were headed somewhere interesting. Then she would repeat the process at the next port. There are also forums for connecting people in this manner. She always got food on board, and sometimes paid a stipend at the end of the trip. After a year and a half of adventure in dream locales I don't think she was out-of-pocket more than a four figure sum.
Certainty, and minimizing risk is expensive, but accepting the opposite can open up a lot of opportunities.
I've met a few people doing versions of this. It's definitely possible to sail round the world on 2-6 person boats and come back with more money than you started with.
You can't skip over the cost (both time and money) of learning to sail, though. It's not a cheap hobby, though you might get lucky and find someone to take you on for free.
Certainty, and minimizing risk is expensive, but accepting the opposite can open up a lot of opportunities.