When you barter and the traders are eager for your 1x Teladianium or 1x Vita Kai etc....

Always go to the Merchants tab then click on each merchant to see what they will sell

Then click on what you want them to pay (The goods THEY have in stock; that you want) NOT on your goods that you are offering.

If you go to the first tab you will only get what the merchant is offering and that is usually a much smaller profit to you and a much bigger profit to him.

eg. I was offered 216 x Energy for my 1 x Space Weed
[worth about 2200 in that sector or around 4000 if I search around]
I didn't think that was enough!
So I went to the Trader and told him No thanks ... but I'll take all your 1389 x Energy for it. He very kindly accepted!

That equals 1389 x 12 [minimum I can sell locally] 16668
In reality I'll sell for at least 17 = 23613 nearly 7000 more profitsss ;)

When setting up to do bartering it is often best to have one large TS with at least 10,000 cargo space and a smaller ship with a store of items that are in short supply in that sector.

You as pilot/trader need to be in the ship that is doing the actual barter. You can change ship from one docked ship to the other and can transfer the needed goods too.

There is no reason why you can't take several TS to the Station and hop from ship to ship selling your smaller cargo items for much more than you may get elsewhere. E.g. the NPC's are wanting Crystals and several NPC's are offereing really good deals if you barter for goods instead of credits.

Place the requested amount of Crystal in the TS that has the cargo space to hold the goods offered ny that NPC then move to the TS. Then open the dialogues with the NPC and close the deal. Move back to your Crystal holding ship and look for another deal.

Happy bartering