4Game

The only real things that would have to be implemented to make this happen are:

• Traders would need to have "secret" values for each barter good, and that value should change based on how many people give them what over time, as well as whatever random factors BSG wants to throw in on a whim. You'd try to buy a pile of stuff from them and instead of just paying in cash you'd have to keep flashing different groups of barter goods at them until they were happy. Honestly, if it doesn't work right, it would be easy to anthropomorphize the traders and just be like "fuck the rapist she wont give me shit right now" or "go stock up on meds now Therapist is practically giving everything away — she must have just gotten a thicc shipment!"
• When you barter with/for stuff on the flea it shouldn't remove FIR. Non-FIR stuff should only be able to be traded with traders; it would at most buff people shoving stuff in their ass very slightly but allow market-savvy people to play the market (which is an aspect of 12.10 that is sadly [but understandably] missing compared to previous iterations, and would probably help with liquidity in a fiat-less market). Instead of FIR, maybe "dirty" goods would have a different flag, and only be able to trade w/ Fence for really diminished value

Thats it; just do this and then see what happens! The meta will shake itself out and we will see what the real economy in tarkov would look like. The next step would be letting people have "booths" in the flea instead of listing things one at a time (but I am sure this is tied to much more complicated late-dev projects that will MMO-ify EFT over time).