I have made every attempt to keep this mod as compatible as possible with all other mods, and it should be fully compatible with nearly every mod out there. There are a few features that may conflict, but these can be toggled off to maintain compatibility. The features will work just fine with merchants added by other mods (assuming they've been placed in the proper factions). In fact, while this mod does work very well on it's own, my primary intention was to create a mod that would compliment and enhance existing mods that already overhaul Skyrim's economy.
PERKS - Trade & Barter allows you to adjust the value of the Investor and Master Trader perks. This should work even if you have another mod that alters the Speech tree. Options: set either perk to 5000 max. You can set independently adjust the amounts required to invest and the amount of gold the merchant receives. However, when you make the initial investment, this money will be available until spent. Trade & Barter also adds to the Investor Perk by providing merchants with increased inventories when you invest in them. Increased inventories are unique to each individual merchant.
In his analysis of barter between coastal and inland villages in the Trobriand Islands, Keith Hart highlighted the difference between highly ceremonial gift exchange between community leaders, and the barter that occurs between individual households. The haggling that takes place between strangers is possible because of the larger temporary political order established by the gift exchanges of leaders. From this he concludes that barter is "an atomized interaction predicated upon the presence of society" (i.e. that social order established by gift exchange), and not typical between complete strangers.