Re: Making a living as a liveaboard
Run drugs, guns and liquor. When I was in the Coast Guard that seemed like the business most live-aboards were in. We were constantly being reminded to not overlook Ma and Pa on their sailboat when doing boardings. We would frequently review cases where a sailboat was boarded and the 70+ year old Grandmother and Grandfather had large quantities of illegal drugs on board.
I think from a practical standpoint unless you work part of the year and cruise the rest or are independently wealthy, bartering is the only real way to get the items you need like fuel and provisions.