У просто iron есть цена в табличке

Trade
Guilds, nobles, and royalty regulate trade. Chartered companies are granted rights to dam rivers in order to provide power for mills, to conduct trade along certain routes, to send merchant ships to various ports, or to buy or sell specific goods. Guilds set prices for the goods or services that they control, and determine who may or may not offer those goods and services. Merchants commonly exchange trade goods commodities without using currency. As a means of comparison, some trade goods are detailed on Table 7–3: Trade Goods.

SELLING LOOT
In general, a character can sell something for half its listed price. Characters who want to upgrade to better armor or weaponry, for example, can sell their old equipment for half price.
Trade goods are the exception to the half-price rule. A trade good, in this sense, is a valuable good that can be easily exchanged almost as if it were cash itself. Wheat, flour, cloth, gems, jewelry, art objects, and valuable metals are trade goods, and merchants often trade in them directly without using currency (see Table 7–3: Trade Goods). Obviously, merchants can sell these goods for slightly more than they pay for them, but the difference is small enough that you don’t have to worry about it.