The Pilot’s Book · Trade
Contracts and merchants' runs
«Quests» → «Contracts»: the port's contracts and bounties, the merchants' runs (buy here, deliver there by the deadline) and the Admiralty's board.
In the port window open «Quests» and the «Contracts» chip: everything for the trader and the hunter on one page. 
«Merchants' runs»: buy the lot here at the market price and bring it there by the deadline. The house pays its price and a bonus for speed — all of it while nearly half the time is left. Deliver, and it offers the next leg; the fifth closes the chain with a present.
See also
The market and pricesEach port has its own prices, and they change every 8 hours. ▲ and ▼ show the trend; luxuries swing the most. Buy cheap here, sell dear there.3 steps
The exchange and the auctionIn bigger ports the «Exchange»: forwards, buy orders and the bank. In the Free Harbors the trophy auction: 10-minute lots, the house keeps a tenth.5 steps