Crew/ short term visa for US citizen in French Polynesia

Hello there, i am leaving to central america in about a week and am in the works to locking in a crew postion from panama to french polynesia. I have been told by some that coming in on a boat you are required to have a return plane ticket, a short term visa in hand already, and even medical insurance. Are all the technicalities that can be worked out when you arrive with a passport and some cash? Or must you apply for a visa before hand from a consulate? I am leaving the states in about a week but not leaving central america untill maybe early march. How could this work,. how does this work? Thanks for any help or experiences.

colin

Reply posted to cross-posting in 'Life on the Ocean Wave'.