The deal is, if you're going to barter and you want to actually get the skills to make it worthwhile, you need to commit to it. You need to barter for as much as you can, and you need to develop your own places where you can run and grab things quickly for bartering. I'll give you a few examples of some of my places, but everyone will find their own places based on their style and where they tend to hang out in game. The thing is, you really need to keep a sharp eye out for things of value, and you need to be vigilant about it.
Rings. Rings are generally of SOME value, since they are type jewelry and those types of things tend do carry at least a few hundred copper of value, at a minimum. Grab rings, gems, bracelets, as much lightweight stuff as you come across, and use it for buying food, healing refresh when you don't really need to, etc. It's okay if it's just low level low value crap, just grab it and refresh those legs! Rings are also light, generally can fit a ton in a bag, and jewelry is given a higher rate of barter than most non-vendor type items. Even if you only get a pie or three for your trade, you are bartering and getting better at it.
Artifacts, wands, scrolls and the like. Artifacts especially seem to have a lot of value, which is awesome except there are only a few vendors that will buy them. However you trade that sphere from the trunk near the Planar Sanctum for some high end food or venoms and you'll get a handful in return. Wands and scrolls likewise generally hold a decent value. Magic ain't cheap. They also tend to be lightweight. The wands and items inside the Planar Sanctum are excellent for bartering for heals, food, cheaper scrolls and potions from some vendors, and can be sold for a decent amount of change too, bartering aside.
Azuremain. Azuremain is a GOLDMINE. The robes, weapons, wands, scrolls and all have a quite decent value, and are almost always laying all over the ground. Run up, grab as much as you can carry, run to barter, wash, rinse repeat. The cavefisher dung from the orc is also worth exactly one venom of detect invis as well, and weighs 2 ounces. I always carry a bunch of shit in a bag with me, and every time I go to barter for venoms I whip out my bag of shit, and get one more. This way no matter how bad things get, I can always get at least ONE venom in a pinch.
Gems. There are about a dozen gems farmable in 2-3 minute increments just a few steps away from Galadon. Not super value but light generally speaking, barterable for some of the better heals or premium foods, or sellable outright if you're not bartering.
Enpolads. Near every single item in the garden is high value. All of it. Extremely high barter value there between the weapons, gear, and clothing. This was my bread and butter for a long time as one of my characters after it went in. Really just stupidly overpriced stuff here.
Owlbear feathers from Dranettie. It's been a while, but they used to be VERY valuable and farmable all day long.
Basically there are some high value items you will come across from time to time that don't LOOK impressive or do much of anything, if anything at all, and you need to grab them when you can for bartering purposes. Make a habit of loring or iding everything, and keep values somewhere in mind. Remembering "Hey that worthless looking robe of worn burlap is worth 15k" can really be a help when you decide you want to get the full 8 rabbit pies for your barter.
