I won't say well-described, it's one page, but at least I know that if I have a load of iron rods, I probably want to look at going to Barathi and Sha Ka Ruq to get the best deal, and not Viridia.

They've got a "Make this roll, and you get X wealth" basic allows you to pay wages and supplies, and the farther up to go, the more wealth you have to spread around.