Use our virtual trade currency called Trade Dollars to purchase anything you want within the exchange. Our Trade Dollars are equivalent to the value of the Canadian Dollar. Our members are asked to price their products and services within the exchange at fair market value. This means you pay exactly the same amount for the offered goods and services as you would in the cash world. The only difference is, you now have the ability to buy things at a discount or at your own cost of doing business!
As Orlove noted, barter may occur in commercial economies, usually during periods of monetary crisis. During such a crisis, currency may be in short supply, or highly devalued through hyperinflation. In such cases, money ceases to be the universal medium of exchange or standard of value. Money may be in such short supply that it becomes an item of barter itself rather than the means of exchange. Barter may also occur when people cannot afford to keep money (as when hyperinflation quickly devalues it).[14]
Throughout the 18th century, retailers began to abandon the prevailing system of bartering. Retailers operating out of the Palais complex in Paris, France were among the first in Europe to abandon the bartering, and adopt fixed-prices thereby sparing their clientele the hassle of bartering. The Palais retailers stocked luxury goods that appealed to the wealthy elite and upper middle classes. Stores were fitted with long glass exterior windows which allowed the emerging middle-classes to window shop and indulge in fantasies, even when they may not have been able to afford the high retail prices. Thus, the Palais-Royal became one of the first examples of a new style of shopping arcade, which adopted the trappings of a sophisticated, modern shopping complex and also changed pricing structures, for both the aristocracy and the middle classes.[18]

^ Homenatge A Catalunya II (Motion Picture). Spain, Catalonia: IN3, Universita Oberta de Catalunya, Creative Commons Licence. 2010. Retrieved 2011-01-15. A documentary, a research, a story of stories about the construction of a sustainable, solidarity economics and decentralized weaving nets that overcome the individualization and the hierarchical division of the work, 2011.
In a small economy where individuals specialize in trades, they may find the process of setting up a centralized currency and maintaining it an unnecessary burden in order to trade. One option may be to use a commodity to exchange value between parties that want to trade goods or services and this is why gold and silver have been useful forms of currency in many cultures and times. Another option may be to use a barter system to trade.