Markets

Olympia: The Age of Gods PBEM (Oct 4 2000)

## 7.2: Markets

        The story is told / Of the power of gold
        And it's lure on the unsuspecting.
        It glitters and shines / It badgers and whines
        And constantly needs protecting.

            The Power of Gold, Dan Fogelberg/Tim Weisberg

Nobles issue `buy` and `sell` commands to indicate their desire to trade goods. Every trade must be between a buyer and a seller. Whenever a compatible `buy` and `sell` request are found, the trade will be executed.

Trades are only matched in cities, where merchants gather at the local bazaar to swap goods, and in Trading Guilds, where professional merchants meet to buy and sell trading goods. Trades are only made at the end of the day, so if you wish to trade you'll have to stay in the city or the Trading Guild for at least one day.

(Note that nobles are always free to use the `give` command to exchange items, regardless of where they are. But `buy` and `sell` orders are only matched in cities.)

A buyer indicates what he wants to buy, how much of it he wants, and the most he is willing to pay. A seller indicates what item is being sold, how much of it is to be sold, and the minimum price he will accept.

Example: A noble who wants to buy five iron [79] at no more than 10 gold each issues:

      > buy 79 5 10
      Try to buy five iron [79] for 10 gold each.

A noble wants to sell five iron [79] at no less than 8 gold each:

      > sell 79 5 8

A trade occurs if there is a buyer willing to pay a seller's minimum cost.

In cases where there are multiple buyers and/or multiple sellers, an "auction" takes place. An auction works as follows:

The buyer willing to pay the most for a product buys as many as he can at a price just above that of the next highest bidder. If there is more than one seller, he buys first from the seller with the lowest asking price. When he is satisfied, the auction repeats with the next highest bidder. If there are no other bidders for an item, the buyer pays the seller's asking price.

For example, suppose a market contains the following:

      Noble A selling 2 horses at 75 gold each.
      Noble B selling 2 horses at 80 gold each.
      Noble C buying 1 horse at 88 gold each.
      Noble D buying 3 horses at 100 gold each.
      Noble E selling 3 horses at 150 gold each.

Noble D would make the first purchase. He will buy horses at 89 gold each (just above the next highest's bidder's price of 88 gold each). He purchases first from A and then from B. Next, Noble C makes a purchase. There are no other bidders, so he buys a horse at the seller's asking price. Noble E is not involved, since his asking price exceeds all the buyer's prices.

      Noble D buys 2 horses at 89 gold each from Noble A.
      Noble D buys 1 horse at 89 gold from Noble B.
      Noble C buys 1 horse at 80 gold from Noble B.

Note that order in the market makes no difference. The first sale will go to the noble willing to pay the most.

Trades only happen at the end of the day. Nobles passing through a market without being there at the end of a day (e.g., moving in and out of sublocations such as towers) will not transact any trades.

If a buy or a sell order can't be matched with pending trades from other units in the city, it will become a standing order and remain in effect until executed or canceled. To remove a pending trade, issue a trade with units of zero:

      > buy 79 0
      Cleared pending buy for iron [79].

Note that the buyer and seller can't specify what noble they will deal with. They will trade with any unit that has a matching `buy` or `sell` order.

- Market report
- City purchasing
- Resolution of trades
- Partial trades
- Sales Tax
- More market examples
- Trade goods