Vendor can trade only goods from his inventory. Some of them can be only bought, only sold or both bought and sold.
Money[ | ]
There are three things which alter vendor's money:
Trading with Keeper
Daily, vendor specific constant profit
Daily trading with the global market
Constant profit and trading with the global market happens at the end of every day.
Trading with global market[ | ]
At the end of every day game simulates vendors interaction with the global market. They buy deficient and sell surplus goods, it is defined by good's base quantity.
Vendor will trade with the global market if good's quantity is not within +-5% of base quantity. Example: Farmer's flour base quantity is 100, he will trade flour with the global market if flour quantity is less than 95 or more than 105.
Vendor will sell to the global market if good's quantity is greater than base quantity + 5%. He will sell 5% of good's quantity rounded up with a maximum limit (limit seems to be 25% of the base quantity rounded up). Example:
Farmer has 104 flours, he will not sell flour to the the global market.
Farmer has 153 flours, he will sell 8 flours to the the global market.
Farmer has 162 flours, he will sell 9 flours to the the global market.
Farmer has 500 flours, he will sell 25 (limit) flours to the the global market.
Farmer has 800 flours, he will sell 25 (limit) flours to the the global market.
Similar with buying from the global market.
Optimal Trading with vendor[ | ]
Due to the nature of vendor's interactions with the global market daily demand for specific good will vary. It will vary even more with longer time periods. However, it is possible to calculate minimum daily demand and use it for calculations for longer time periods. Example: Farmer's flour base quantity is 100, daily demand for flour will be 5% rounded up, it is 5 flours per day.