The three Commerce policies are as following with values taken from the first Egypt stream:
If you switch to transaction taxation, it is possible that you lose copies of goods and that could mess up your trade routes alot which mean you lose huge amount of Power and Commerce income. Free trade have the opposite issue that if you use the extra trade routes and then switch away from it you going to lose several trade routes and thus the Power you invested into these.
It seems to me that Commerce policy will be something you set at start and then forget about it because of all issues than can be caused then switching it.
- Transaction Taxation: +15% Commerce Income Modifier & +2 Slaves Needed for Surplus Trade Good Production
- Trading Permits: No Modifiers.
- Free Trade: -15% Commerce Income & +1 Trade Route Per Province
If you switch to transaction taxation, it is possible that you lose copies of goods and that could mess up your trade routes alot which mean you lose huge amount of Power and Commerce income. Free trade have the opposite issue that if you use the extra trade routes and then switch away from it you going to lose several trade routes and thus the Power you invested into these.
It seems to me that Commerce policy will be something you set at start and then forget about it because of all issues than can be caused then switching it.