I would suggest making use of our knowledge gained by trading map information/trade rights with foreign factions. It would make sense both Ic and OOC to gain knowledge of what resources are available in said faction through diplomatic /trade exchanges. And requiring trade rights would also mean that our merchants have been granted a patent to trade in said factions.
Ie, if we have established diplomatic relationships with Byzantium, I'd be allowing trade of resources within their territory.
It is difficult to "not know" where the resources are in game as we're all veteran players but by creating the necessity for an established link, we somewhat limit ourselves...
So until we've conquered Egypt and the Moors, there should be no trading of the goods that bring so much cash (ivory, slaves, sugar...) as I think all diplomacy with them was forbidden (though that may not have been re-enacted this term).
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