Buy and sell a bit (also buy skins from Ladoga and sell in Stockholm, etc..), then make a workshop or two and join the guild. If you can, get a convoy and send it on an expedition to sell more iron goods. Profit.
Choose three or four towns that you will concentrate on building up, but I suggest Stettin to be one of them, as its grain and beer prices are great.
I'm suprised you didn't mention Wine from Cologne. I've made boat loads of cash that way. I've also found that doing triangle trade between Reval, Lagoda, and Novgorod pays well.
The next run is to supply Lubek with Iron Ore from Aalborg, Oslo, Cologne, and Stettin.
Another profitable idea is just to send a ship to as many towns as possible to buy any cargo they can for cheaper than the average selling price in Lubek, and return it there. That also greratly improves your standing in your hometown.
ie: Lubeck(r) to Malmo, Aalborg, Oslo, Bergen, Edinburgh, Scarborough, London, Bruges and Cologne; buying almost goods. (beer < 45, iorn ore < 900, wool < 1100, pottery < 200, wine/cloth < 300, etc)
Making meat and leather in Aalborg and Malmo os also very profitable, but most of the demand for them in Lubeck may be taken up by other traders. Other towns greatly appreciate those goods, which are valuable; meat purely as gold, but leather makes weapons.
If you haven't been actively pirate hunting for a while, they start getting more ambitious this way. After assembling a navy of a few hulks, you can send them to track down the sneaky buggers. Which can be quite fun... (convoy with 10 ships; battle; convoy with 11 ships; battle; 12,13,14,15, repair)
Bricks can be produced very cheaply in vast quantities, but mostly they are just used to build your own buildings.
The Prince of your hometown and any towns you build will also buy timber and bricks for relatively reasonable prices. Spices too, once you explore into the mediterranian.
Its also convienient to have a standing navy of 10 - 15 hulks to prey upon enemies (either pirates of fellow traders) when the seaways start to get crowded.
Also, as your reputation in towns increases and you become a patrician and the Alderman, towns will prefer to trade with you, and will offer you better prices on some goods.
Another way to make some easy cash is to hand out loans. It takes a while, but a loan with even the lowest interest rate may double its value over the course of a year. And you can give out loans in any town you come to, so you can recoup massive amounts of money, and even cargo and ships if they refuse to pay. (Not recommended in towns where you want a reputation)
But just try what works best for you.
What I do is start in Lubec and build five pitch works, 4 brick works and late 5 or 6 sawmills. This gives me ample resources to build houses, wells or whatever. I also stash all of the cloth, pitch and hemp in my warehouse then when I have enough, I build a Hulk, then progress from there. I also loan money and get a lot of boats from those who fail to payback their loans. A lot of these are wrecks but can be upgraded and repaired. I arm my ships pretty well to capture and ward off pirates. I eventually wind up with five or six hulks and cogs, and sometimes a dozen or more sanakas(however you spell that,) and crayers. Of course I do use a trainer. I use Game Cheater, which is one of the best on the market as a money trainer. I can start with 999999999 and it will add everytime I spend, so I never run out of money. For those of you who are having a hard time, try this trainer and I think it will open up a whole new world for you.
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