How to Tax People
When you setup a trading post and sell goods, the money earned is Regional Wealth you can see this on the top bar on the UI, toward the left.
This is the combined wealth of the people. Everything bought or sold at the traders, or built on plots of land such as Chicken Coup upgrades or Goat upgrades uses Regional Wealth.
When you build a Tax Collector, you can only earn tax income if there is regional wealth to take from the people. 0 regional wealth means 0 taxes. For the sake of the demo, you do not need to worry about the Church tithe. Influence cannot be spent.
Why tax people? You need to gain Personal Wealth (can be seen in the top right of the UI) to pay the King. You only need a small amount in this demo. Generally, let the people keep their regional wealth and upgrade their houses instead as for the demo, you don’t need personal wealth as there’s no armies to fund.