Yacht Careers

How do you become a yacht broker? What citites/states are best to sell in? Help please!?

My fiance wants to change careers and knows lots about boats, he grew up on one and worked on them his whole life. He would like to become a yacht broker to sell them but doesn't know where to start. Do you need a degree or any kind of special education? What are the best cities/states to work in? Any info would be appreciated. Thanks!
He knows Southern Florida & California are good spots, we were wondering if there are any others along the coast that are good also. Keeping our options open.

southern california or south florida is the place to be for this.