Negotiating was pretty interesting in Oblivion, but I kind of prefer the way it worked in Fallout 3. It just makes the whole process of buying/selling so much simpler.

I found the buy/sell process fairly mundane. Although, I did have this system where through divine intervention or awesomeness on my part, I ended up with all of the other person's stuff AND their money.

Anyway, I think the negotiation aspect would just generally improve the game.

This is an aspect of TES which i genuinely thought was really good. I would love to see negotiation of selling/buying prices based on the barter skill.

I have a couple of characters who are based on the Scavengers one randomly encounters all over the CW, and they tagged those exact skills. I also deliberately concentrated on raising those skills to the cap from the beginning, and as a result I was able to afford the more expensive items from the start. Since I left their combat skills low for quite a while it was just as well I could buy the stronger weapons, because I needed them in order to do enough damage to many opponents.

Unfortunately, the bottomless supply of high-end equipment taken from dead Enclave patrols quickly ruins the already fragile balance of the economy and in the process kills the RP, so these characters do not get much play time anymore.

The only truly effective solution to the 'loot problem' is to eliminate the endless supply thereof, but I highly doubt that will be done as the resultant wailing would be of legendary proportions. There is also the Oblivion method, wherein there is a built-in ripoff factor and a higher Barter (Mercantile in Oblivion) reduces that amount until you almost completely remove it at max skill and trader disposition. Unfortunately, vendors there have a strict limit on the most they will pay for any given item, so you lose massive amounts of value if you sell top-end loot.

And Morrowind too, I don't recall how barter works in Daggerfall, but yes, you were probably thinking of one of the Elder Scrolls games when you expected to actually be able to change the price of items you sell or buy yourself.

I never bothered too much with barter skill in Fallout 3, though, as there didn't seem to be much need for it, considering that there was little need to buy things, and when you did want to buy something, you'd probably have no trouble getting enough caps to afford it. If Obsidian wants to make barter more useful, they would need to cut down on the amount of caps you're likely to get in the game and make sure that there are things worth spending them on, so players would have a reason to choose to invest skill points in barter when they could be investing them in some other skill instead. Which I hope they can do, after all, there's really not much point in barter being a skill at all if no one wants to actually take advantage of its existence. Especially if Obsidian is making it harder to be good at everything in the game, as no one is going to bother spending skill points in barter if the amount of skill points is more limited than in Fallout 3 unless barter is a more beneficial skill to have in the game.