Port Royale 2/Ordinary Sailor
Ordinary Sailor is the first rank that you will gain, it gives you the ability to buy a permit in any town as long as you have a 100% Trading Record with that town. you can also control a second ship and you can also do quests, go to the tavern and people will tell you clues, sell you treasure maps or give you missions. You are probably best to stick with trading although you could buy one or two buildings if you plan on trading mainly in the game. If you plan on trading (or just need a good way to make money while doing quests, you may want to set up a trade route, this will make your ship automatically trade and make some money.