For instance, each time Apple releases a new version of the iPhone, the second-hand market for older versions of the iPhone enjoys a flurry of activity. However, you do have to be as careful with the barter of used goods as you would be with the purchase of used goods. Be sure everything is in working order and shows no signs of significant damage.

Economic historian Karl Polanyi has argued that where barter is widespread, and cash supplies limited, barter is aided by the use of credit, brokerage, and money as a unit of account (i.e. used to price items). All of these strategies are found in ancient economies including Ptolemaic Egypt. They are also the basis for more recent barter exchange systems.[15]
Although, as a general case, a ship unlucky in falling in with whales continues to cruise after them until she has barely sufficient provisions remaining to take her home, turning round then quietly and making the best of her way to her friends, yet there are instances when even this natural obstacle to the further prosecution of the voyage is overcome by headstrong captains, who, bartering the fruits of their hard-earned toils for a new supply of provisions in some of the ports of Chili or Peru, begin the voyage afresh with unabated zeal and perseverance.
Inevitably some people may feel like they were taken advantage of. One way to diminish inequities is to engage in dollar-for-dollar trades. For example, if you would like to trade your housecleaning service for someone’s couch, try to break down the goods and services to the dollar amount. If the two of you decide that the value of the couch is worth $200, why don’t you supply a gift certificate for $200 worth of housecleaning services? It’s a wise course and ensures all parties know what they are getting and what they are offering.
When barter has appeared, it wasn’t as part of a purely barter economy, and money didn’t emerge from it—rather, it emerged from money. After Rome fell, for instance, Europeans used barter as a substitute for the Roman currency people had gotten used to. “In most of the cases we know about, [barter] takes place between people who are familiar with the use of money, but for one reason or another, don’t have a lot of it around,” explains David Graeber, an anthropology professor at the London School of Economics.
During economic downturns, when there is a keenly felt shortage of jobs and cash, people have historically adopted barter systems. The world’s most established bartering-style system is Switzerland’s wir: the German word for “we” as well as the abbreviation of Wirtschaftsring, which translates loosely to “economic circle.” In 1934, the economy in Switzerland had tanked—as it had in much of the world. Two businessmen who were facing bankruptcy, Paul Enz and Werner Zimmermann, gathered 15 of their associates in Zurich and hashed out a solution: a mutual credit system.