Instead of having a different trading post in each settlement or a single/global trading post, I propose something I call, “Faction controlled Trading Posts.”
Explanation:
1.Three markets would exist in the game.
2.You can only visit a Covenant market while you’re in a Covenant controlled region, same with the other two factions. The more regions a faction controls, the more accessible its contents are.
3.You can buy from any market, but to sell in a “faction controlled trading post” that’s not your own, will be costly.
The reason I think it’s a good idea is because it gives an incentive for players to fight for regions. It also makes it harder for bots to sell items if the regions market controller changes. It also puts the trading posts on the outskirts of the map to use.