There are two types of coinage in Avalon: hard currency and gold pieces. Hard currency is real and can be a very serious business. Hard currency cannot be stolen and is protected with absolute guarantees. Gold pieces or gold coins are in-role in-game coinage and these are used by the land's shops and quests and treasuries.
Hard currency is based on "real world" purchase and uses the CROWN as its name or Avalon crown for accuracy. The CROWN is the basis of the realm's four major city-state currencies: the Mercinaen shilling, the Thakrian ducat, the Silverfallian florin and the Parrian doubloon. The value of the city currencies is based on the world economy and goes up and down. The CROWN has a changing value but can never go below one to one on the "real world" US dollar.
Avalon's many banks are able to hold accounts in gold, in CROWNS and in the local city's currency: shilling, ducat, florin or doubloon. It is not necessary to play with city currency and speculation is part of the WEALTH meta-game, loved by some, ignored by others. See HELP FIVE for meta-game in Avalon.
Gold coins, as the main convenience coinage of the quests, treasuries, cities and shops of Avalon, are much in demand and you will no doubt build up many in your course of your adventures. They are useful at first for the purchase of essential goods and equipment from the shops - usually in your home city - like food and armour and potions and protective runes.
You may acquire enough gold to invest in a steed or better yet a house - modest at first but there are great palaces and towers with extremely high value, managed by the city governments and bought or allocated to the greatest heroes of the time. It is also possible to turn merchant yourself, either travelling and trading like a pedlar or acquiring a shop to sell your wares. This is a popular avenue for the Loremaster, Ranger and Druid professions as these classes produce much that is desirable as part of their guild skills. It is not uncommon for a Thief to own a shop though it may be wise not to inquire too closely into the origin of its goods for sale.
If you carry around your gold coins and you acquire a sizeable stash you will become vulnerable to accidental loss or burglary. It is a good idea to bank excess money (see HELP BANK). Bank accounts in gold coins are managed by the cities and the State Ministry/Chancellory with interest decided by the government and bank charges (if any) set by the ministers.
The four great city royal families own the banks: Mercinae's King Thandrades is the patron of its Royal Bank, Thakria's Emperor Periam owns the Imperial Bank of Thakria, the city of Parrius has Bank Augustine after its monarch Lady Augustine, and Silverfalls' reconstructed bank is backed by the family of Count Athelstone - monarch of the successor city to Springdale.
The realm's other banks, like the Gantian Bank, accept accounts in gold coins but primarily use CROWNS and serve as exchanges the city currencies at current rates (type RATES to see up-to-the-moment exchange rates). Knightswood and Oakwood End Fortress have private banks whose rules are defined by the players in charge of Knightswood and Oakwood's End respectively. Consult them direct for details.
All of these banks run accounts in CROWNS for investment and interest gain as well as the city's own currency. Accounts in CROWNS and city coin - hard currency accounts - have no charge for use and gain interest as time goes by. See HELP CROWNS and HELP INTEREST for details. It is a service and it can be part of your Avalon life or not, as you choose.