Hello. This is Jim. Jim runs a country called Jimson in an IOT. Jimson is a producer of fish, cocoa, and gold. Jimson has a Market.
And this is Jones. Jones runs a country called Jonestown in an IOT. Jones produces cocoa, beer, and rice. Jones also has a Market.
Because top-down mechanics for trading commodities is difficult, and broad simple markets can sometimes cause weirdness, the GM has opted for a go-between by making it so some players can open a Market. Players can buy and sell from Markets of their choosing. For example, Jim, when he produces fish, can sell all the fish he wants to his own Market no matter what.
But what if Jim wants to sell fish on Jones' market? Well, to do so, Jim needs Trade Power in Jonestown. For an outsider to buy and sell on his market, they need at least 1 Trade Power. The more Trade POwer Jim has on that market, the more Jim can buy and sell on that market.
But how is that limit DETERMINED? Well, when Jones buys goods off his market, he creates demand. If he, plus others, spend $100 buying goods on the market one turn, then the total limit is 100.
There is currently 20 Trade Power in Jonestown. Jim has 1 Trade Power. Therefore, Jim can buy/sell up to $5 [(1/20)*100] worth of goods from/to Jonestown's market.
What does the GM do?
Each player would have X number of Trade Power, which could be based on trade units or a stat or whatever the GM wants. This trade power can be put into any country, with bordering countries potentially getting a bonus. For example, I have 5 TP. If I put all 5 TP in my neighbor, it is actually 10 TP. The GM could throw in trade agreement stuff in here as well.
The GM would list Market Prices like in an EQNES, but for each market. The GM would add one additional line to each market.
Trade Power Limit: $X
This would represent how much one could buy or sell.
For example:
Rooseville Market
Food: 46 Gold for 1 Food
Water: 6 Gold for 1 Water
Lumber: 64 Gold for 1 Lumber
Ore: 1 Gold for 1 Ore
Swords: 25 Gold for 1 Sword
Spears: 25 Gold for 1 Spear
Crossbows: 57 Gold for 1 Crossbow
Horses: 56 Gold for 1 Horse
Trade Power Limit: $200 per Power.
My orders would could look like this if I have 1 TP in Rooseville.
Buy 2 Horses from Rooseville Market ($112)
Sell 3 Swords to Rooseville Market ($75)