It depends a lot on what the goods were, where they were going, etc. A lot of voyages were speculative and instead of wages, the crew would get a proportion of the profits from the voyage. How big a share you got was determined by your rank. So, you would sign on to sail to Goa and pick up spices. You'd go down and hopefully not die, then come back, or jump ship if there was a more lucrative looking offer, and sail back. When your cargo of spices are sold, it's accounted for and you're given an allotment commiserate with your rank and whether and for the length you spent on the ship during that voyage.

The other poster mentioned advances. Those became more essential and expected over time. Sailors needed money to support their families while they were gone if they had one. They had to settle debts. Etc.

Also, some things we don't count as wages were considered wages back then. The most important was the food and beer rations. Nicer food/beer was seen as a better wage. They also had the opportunity to pick up some rare goods to take back and sale on their own.

Also, if the vessel had passengers, the crew had opportunities to earn tips to supplement their wages.

There's a scholar named Lewis Fischer who did a lot of work on this topic. He's got a couple books out and if you've got JSTOR you can find papers.

Ultimately, yes Masters of the ship (merchant ships most often had just the master) carried some money with them to pay expenses

but for your exact cases situation is more complicated. Crew was usually hired for specific journey and payment was agreed to be done at end destination which often was at return to original port (to make sure your crew stays all trip). Some advance would be given before sailing (e.g. 4 months wages in some exploratory voyages). Payment would then be settled in relative safety and availability of funds in familiar port.

Additionally "banks" would often be involved and instead of actual cash, bank letters of exchange could be given. Not sure how widespread that would be but it was definetly an option to make sure not much cash was carried on the trip itself. If nothing else the master could withdraw cash at the port from a bank if he needed cash for wages.

The same goes for cargo, banking and exchanges were the norm. Just wanted to point out by then there was a separation of shipping and trading so while the master could buy and ship his own goods, he may just as well just sell space on his ship and let others deal with buying and selling goods

You might get cheques or letters of credit trading between European ports, banking had advanced that much by then. But ships trading with distant countries took gold or silver (depending on what was most valued) to pay for cargo, if they couldn't pay from sales of the goods they sold on the outbound journey. Crew would be payed when the ship docked, sometimes they'd only get their full pay when the ship reached its home port.

All excellent information for me. I found Shipping and trade (1750-1950) on Internet Archive with much of interest.