I've designed this to be a very lightweight mod. It uses a series of carefully conditioned perks to accomplish nearly all of it's changes. The only script included in the mod is the MCM script that controls the menu options, so the mod will not cause any performance hit or save game bloat, and can be uninstalled cleanly at any time. To uninstall, go to the Mod Configuration Menu and click "Stop Mod." Once the mod is deactivated, simply delete the mod from your data folder.
SOME SUGGESTIONS - With all these different variables, you may be wondering what the best settings are to achieve a good balance in your game. Of course this will depend on what you want. Many people (myself included) like to make trade more difficult. I also like to set the barter settings relatively close to de-emphasize Speech skill and place more importance on the Speech perks.
Barter is a system of trade in which one party exchanges products, goods and services in order to obtain required products, goods and services possessed by another. In a barter system, no money exchanges hands between the buyer and the seller. Instead, both parties to the sale determine how much of a product a fair trade for another product or service. Since people assign different worth to different products, a barter system makes it difficult to decide how much of an item needs to be offered for another for the transaction to become a fair trade. Barter system was largely used long ago before the world developed the concept of currency for the exchange of goods. Nevertheless, the barter system is still prevalent today among nations, corporations, companies, individuals and businesses. The barter system makes trade easier for countries that experience large volatility in currency conversion and for countries that do not have sufficient financial resources, but have large volumes of commodities that can be traded for other commodities.
LOCATION - Prices are lower in smaller towns, but merchants also can't afford to pay you top septim for your goods. Cities are expensive, but there is more money to be made there. Merchants in cities charge higher prices when selling their wares, but they are also willing to pay more for premium goods in order to make sure that their shops stay well-stocked. The five major cities can now have their buying and selling rates set individually to reflect their size, wealth, access to supply and shipping routes, or status as a trading center.

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!

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.
Modern barter and trade has evolved considerably to become an effective method of increasing sales, conserving cash, moving inventory, and making use of excess production capacity for businesses around the world. Businesses in a barter earn trade credits (instead of cash) that are deposited into their account. They then have the ability to purchase goods and services from other members utilizing their trade credits – they are not obligated to purchase from who they sold to, and vice-versa. The exchange plays an important role because they provide the record-keeping, brokering expertise and monthly statements to each member. Commercial exchanges make money by charging a commission on each transaction either all on the buy side, all on the sell side, or a combination of both. Transaction fees typically run between 8 and 15%. 

Stop lugging around old books you won’t read again and trade them for some new reading material instead. Bookmooch uses a points system, so you’ll enter the books you want to give away, get requests from members who want your books, ship from home, get points, and then spend the points on the books you need. While membership is free, you’ll receive .10 points for every book you make available and 1 point for every book you successfully give away. To remain in good standing, you need to give away one book for every two you receive.
David Graeber argues that the inefficiency of barter in archaic society has been used by economists since Adam Smith to explain the emergence of money, the economy, and hence the discipline of economics itself.[2] "Economists of the contemporary orthodoxy... propose an evolutionary development of economies which places barter, as a 'natural' human characteristic, at the most primitive stage, to be superseded by monetary exchange as soon as people become aware of the latter's greater efficiency."[3] However, extensive investigation by anthropologists like Graeber has since then established that "No example of a barter economy, pure and simple, has ever been described, let alone the emergence from it of money; all available ethnography suggests that there never has been such a thing. But there are economies today which are nevertheless dominated by barter."[4]
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).[15]