And that means everything from tuna to stamps to cigarettes has its own unique value in a trade and barter market. — Alexandra Cardinale, Vox, "Why ramen is so valuable in prison," 14 Nov. 2018 European officials were also looking at a barter system that would allow Iran to sell oil, for example to China, and use the proceeds from that sale to purchase goods or technology from Europe. — Laurence Norman, WSJ, "Europe’s Payment Channel to Salvage Iran Deal Faces Limits," 25 Sep. 2018 With unemployment around 9 percent and consumer prices surging, some Argentines are again turning to barter clubs, which first emerged during the collapse nearly two decades ago. — Almudena Calatrava, Fox News, "Argentines seek soup kitchens, barter markets amid crisis," 10 Sep. 2018 This particular search insired Gellar and Laibow to hop on the phone and barter. — Colleen Leahey Mckeegan, Marie Claire, "Sarah Michelle Gellar's Second Act? Disrupting the Food Industry," 18 Apr. 2017 Choco Pies became so prevalent for sale or barter on the streets that North Korea reportedly banned their import to Kaesong in 2014. — Brian Murphy, Washington Post, "The Choco Pie dividend: South Korean firms are drooling at the prospect of business in the North," 17 June 2018 In 1996, amid crippling famine, Ji tried to steal a few pieces of coal from a rail yard to barter for food. — Brian Murphy,, "Could these outspoken North Korean defectors return home?," 11 June 2018 In 1996, amid crippling famine, Ji tried to steal a few pieces of coal from a rail yard to barter for food. — Brian Murphy,, "Could these outspoken North Korean defectors return home?," 11 June 2018 Instead, like many early civilizations, they were thought to mostly barter, trading items such as tobacco, maize, and clothing. — Joshua Rapp Learn, Science | AAAS, "The Maya civilization used chocolate as money," 27 June 2018
The barter system is a type of trade that involves the exchange of goods and services without the use of money as a medium of exchange. Trade, on the other hand, is a broader concept that includes not just the barter system, but also, international trade, commodities trading, currency trading, etc. The main difference between barter and trade is that while barter trade does not involve money, other forms of trade occur with currency used as a medium of exchange. An important point to note is that the invention of trade whether barter or otherwise has developed a useful system under which individuals, businesses and nations can exchange or sell off the products or goods held in excess and purchase or obtain desired products, goods and services. The invention of currency has greatly simplified this process making trade convenient and fair. 

Bartering does have its limitations. Many bigger (i.e., chain) businesses will not entertain the idea and even smaller organizations may limit the amount of goods or services for which they will barter (i.e., they may not agree to a 100% barter arrangement and instead require that you make at least partial payment). But in an economic crunch, bartering can be a great way to get the goods and services you need without having to pull money out of your pocket.

In England, about 30 to 40 cooperative societies sent their surplus goods to an "exchange bazaar" for direct barter in London, which later adopted a similar labour note. The British Association for Promoting Cooperative Knowledge established an "equitable labour exchange" in 1830. This was expanded as the National Equitable Labour Exchange in 1832 on Grays Inn Road in London.[21] These efforts became the basis of the British cooperative movement of the 1840s. In 1848, the socialist and first self-designated anarchist Pierre-Joseph Proudhon postulated a system of time chits. In 1875, Karl Marx wrote of "Labor Certificates" (Arbeitszertifikaten) in his Critique of the Gotha Program of a "certificate from society that [the labourer] has furnished such and such an amount of labour", which can be used to draw "from the social stock of means of consumption as much as costs the same amount of labour."[22]

Let's say that you want to make it more difficult to make a quick profit from the items you sell. So you decide to increase the barter settings to 10.0 and 6.5. At these settings, you will receive only 10-15% of an item's value (vanilla is 30-50%). However, you'll suddenly discover that the cost to purchase items has skyrocketed to 1000-650% (vanilla purchase costs are 330-200%). Maybe this is exactly what you want. If so, congrats, there's no need for you to mess with the Independent Adjustments. However, if you would like to reduce the purchase price to a more reasonable level, then you can use the Buying Prices adjustment to lower only the buying prices without affecting the selling prices.
Even before visiting the Marquesas, I had heard from men who had touched at the group on former voyages some revolting stories in connection with these savages; and fresh in my remembrance was the adventure of the master of the Katherine, who only a few months previous, imprudently venturing into this bay in an armed boat for the purpose of barter, was seized by the natives, carried back a little distance into their valley, and was only saved from a cruel death by the intervention of a young girl, who facilitated his escape by night along the beach to Nukuheva.
I wish I came up with this fantastic idea. SharedEarth is a free site that connects landowners with gardeners and farmers in need of space to grow crops (i.e. starting a home vegetable garden). You can find free access to land in exchange for sharing a little bit of produce with the landowner. In a time of a strong and growing local food movement and concerns about food safety, SharedEarth might just be the most important sharing site of all!