PaperBack Swap is exactly what it sounds like: a place to swap paperback books. Currently, more than half a billion books are available for trade on the site. Just list the books you don’t want anymore and other members will find them. When someone requests one of your books, you just mail it out and then choose any available book that you want to receive. Swapping is easy, and membership is free.
Put a price tag on it. Successful bartering must result in the satisfaction of both parties. This can only happen if the items bartered are realistically valued. If you have an item you would like to trade, obtain an accurate appraisal. An item is only worth what someone is willing to pay for it. Therefore, do your research and look at the "selling" section on eBay to find out what online buyers have paid for similar items.
When you load the menu option, the values you see displayed will be the values currently in use by your game. Vanilla values are 3.3 and 2.0. If the menu is displaying different values, then you have a mod installed which is already adjusting these two settings. If you choose to select a new setting, Trade & Barter will override the settings from the other mod. If at any time you wish to revert the settings back to those made by another mod, simply deselect this setting and reload your game. You will need to reload your game before the changes from Trade & Barter are fully canceled out.
Bartering for goods and services is a centuries-old art. Recently, the idea of trading with your neighbors and within your community has received a big boost and taken on a modern spin. Combining our often-materialistic, ownership-based society with the Internet’s ability to bring buyers, sellers, and traders together, online bartering has sparked a wealth of new sites and communities.

He would have heard of channels and sandbanks, of natural features of the land useful for sea-marks, of villages and tribes and modes of barter and precautions to take: with the instructive tales about native chiefs dyed more or less blue, whose character for greediness, ferocity, or amiability must have been expounded to him with that capacity for vivid language which seems joined naturally to the shadiness of moral character and recklessness of disposition.