How exactly trade income and trade treaties work?

[Edward8D]

Hi,

this is a repost from Discord server. I didn't get an answer there and I am hoping somebody here would know how exactly trade works:

I came upon this when I tried to decide if there is any point in upgrading commerce centers if my only trading partner has free trade agreement (FTA) with me.

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Hi, do commerce center impact money gained from free trade agreement (Or LTA)? As far as I know the purchaser no longer pays for the goods* so they shouldn't have an effect on prices. But maybe they secretly contribute to the trade bonuses part? or they act separately from any agreement and are a side bonus on any transaction made under any agreement including none? Can anyone help me understand this in detail?

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So with free trade agreements partners they don't do anything since state doesn't get any tariffs. Correct?
Or is it like:

Let's say you have maxed LTA. They buy stuff for 1000 credits and you get extra for
a) tariffs: 200 for 20% LTS tariff
b) trade volume: 200 for maxed LTA trade volume at 20%
c) Commerce centers: 400 for 40% version

With FTA:
a) tariffs: 0 for 0% FTA tariff
b) trade volume: 300 for maxed FTA trade volume at 30%
c) Commerce centers: 400 for 40% version


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* EDIT: Just realized this is probably wrong. They probably pay for it, you just don't get tariffs. So the question is how is the extra money generated. Is it like:

Trading partner buys goods worth 1000 credits. How is the commerce center charge added? Is it included in the final price for they buyer? So in order to buy 1000 credits worth of goods in tradecenter with 40% commerce center you need to pay 1400 credits? That would mean the station is less profitable with each commerce tech and thus ships would rather buy elsewhere. Sounds counterintuitive. What about tariffs? Are they included in the final price or generated somewhere else? I think I read somewhere that the extra money generated just appears. That would be the system I described above with LTA nad FTA examples.

It's really hard to make an informed decision on making Trade treaties with partners when the details are obfuscated. There are three income sources listed in budget screen: traded goods, bonus from traded volume and surprisingly fuel has its own category. So I assume trade tariffs go into traded goods category. Probably so do bonuses from commerce centers.

[OrnluWolfjarl]

I haven't tested this at all, but as far as I understand, the private sector is the one paying for trade. I think trade agreements boost the volume of trade that can be done. Possibly they impact the decision of freighters for where they should head to buy things from?

[Nightskies]

Commerce centers do impact money gained from trade. Trade Bonuses income is clearly shown, and the absence of commerce centers reflects this, such as deals at colonies without a spaceport.

It is unknown if Trade Bonuses come from thin air or if the buyer pays the additional amount. I believe it comes out of thin air. It is difficult to test this, as the money exchanged occurs long before resources are delivered or retrieved.

By extension, it is uncertain if trade agreements impact the cost of trade. It certainly influences the volume of trade between empires- at least when compared to *no* trade agreement. It *seems* that FTA does result in more trade, if the circumstances- needs of one and excess from the other- are right.

However, there are *no tariffs*. The price of resources may be inflated to empires with less than a FTA, but calling it a tax would be a misnomer. Because...

The state is the sole owner, buyer, and seller of all resources, at all times.