In the case of ordinary civilians, I'd assume that they are still relying on barter. Most will be either growing their own food and trading surplus for whatever they can't grow or make or being paid in food and goods for their labour.
If they have a surplus they can't trade for something they need, they'll have to trade for something durable of value in the hope they can use it to buy something they need later. This might be ammunition, tools or whatever but they may just have to settle for a knock down price in gold and silver from the local merchant.
I don't see anyone recognising a currency that isn't backed locally by food, fuel or something else tangible. This is how the chit works in Krakow and I don't see it being that successful. Most people will work for food in hand rather than chits because the chit needs you to trust that the government actually has the food to redeem the vouchers. I can see inflation and deflation in the chit being so rampant and trade dependent that it wouldn't be trusted much.
It depends what you mean by trade I suppose.
If you mean day to day survival by civilians: just like most of history, it will be by barter of goods and services, even today that happens a lot although we are a lot more cash dependent. Most civilians won't be popping down to local shops to trade their francs, chits or bottle caps for goods, they'll either be redeeming them for food before a bad harvest cuts the dole or working food and goods in hand rather than relying on a shaky government.
Larger scale trade between merchants or richer people could still rely on gold and silver.
In many ways any government backed currency in early TK2 is effectively an additional tax as it will cost to exchange into whatever scrip is legal in the country. Like many taxes in low information environments, people will be avoiding them like the plague.

Samples of things actually used as currency (or investment stock) in our own real world before the advent of paper currency. The Time frames are from a 25 year old college Economics book I just happened to still have on my shelf

Ammunition (Africa 19th & 20th century)
Coins, usually of precious metals (world wide, from Biblical Times)
Corn (Americas, until European Colonization)
Grain (Persia, Africa, Biblical Times)
Gems, both precious & semi-precious (world wide, from Biblical Times)
Livestock (Asia, Africa, Americas, Europe, Biblical times thru the Dark Ages)
Minerals (World Wide, from Biblical Times)
Nails (Europe, Americas, Dark Ages until the 18th Century)
Rice (Asia, until the 20th Century)
Pepper (Persian and Roman Empires)
Salt (Carthaginian/Roman Empires, still used in India until the 20th Century)
Tulip Bulbs (used as one of the first "Futures investments" in Holland, During the Age of Reason)

These were "barter" items whose value was generally established and set (ie. a chicken is worth six nails) by the society in question. This list is by no means totally inclusive and many other examples probably exist. This was just a small list in one book. It is amazing that so many strange objects could persist as a "currency" well into the 20th Century though.

You are probably correct here. Most average citizans would have spent their gold and silver that they originally had.

Pretty solid reasoning, but I think that you didn't extrapolate from one thing you said - "dedicated merchants might have accumulated quantities of gold and silver to do business with," (and you are correct, they probably would have). But the merchants would also be spending that gold and silver (at least some of it) for more stock. So, merchant buys food for resale from farmer, farmer probably gets some things from merchant that he needs and may very well get some gold and silver also. Farmer has people working for him, probably family, friends, and very possibly some (former) refugees the farmer took in. Farmer is providing food and shelter for everyone (which in T2K is a lot), but these people might need or want some additional items that the farmer can't provide, but that the merchant (or another later merchant) might have, or that the workers could get from someone at the "Trade Market" in town. Now the farmer could hand the workers a busher of whatever is being grown for thm to use to barter, or he could hand them a small amount of silver or gold to buy that extra stuff. So I think that especially by 2000+ if not sooner, gold and silver would be going back out in circulation. At least some. Though there would still be a need for other currency based on some or many of the things mentioned before.

Port Lavaca in Red Star, Lone Star, uses silver backed notes.

Page 17
A barter economy has been replaced by locally printed paper notes backed by silver, which are honored by most merchants within the town or the surrounding camps.

Another big one in the 17th and 18th centuries was molasses, used in rum production. Molasses was a big part of the Triangle Trade system.

And whisky/whiskey in the frontier in the 1780s.

Another area that will affect what players do is what currency is used outside of their own 'home' patch. Every RPG has a standard list of values for everyday items. Verything is valued in gold pieces, or dollars, or credits, but in a post-WWIII or post-apocalypse setting, there could be dozens of different values for the same items. If you want to get into lots of detail, a single currency doesn't cut it. Imagine if your group happily gathers every piece of gold they can, and trades it for what they need, then they travel to another zone. Suddenly their gold is useless and something they'd not even thought about is what the locals want. Different free cities, or regions, may not use gold, or silver, or bottle caps, as currency, or may assign a different value to them. What can be bought for an ounce of gold in Krakow might cost 2 in Ostrava. Five miles further down the road, they might consider gold as just a pretty but fairly useless item, and value everything by weight of tobacco, or litres of 'shine. How the players negotiate values when every few miles someone has a different idea of 'value' can become a major role playing event.

Excellent point, and something I hadn't considered.

I recall in the book "Alas Babylon", honey was used as a 'currency', or at least a valuable trade item and gold and silver jewelry became to be viewed suspiciously because of the possibility they might be radioactive...

Yep. I agree. I have some junk silver stashed away since I'm in the US but if I was in Europe, I'd have gold sovereigns instead.

The Aftermath London adventure has ammo as currency.

Depends on where you are and who you're dealing with.

Spartan117 was asking about trade and I threw together some rules for him to use with V2/V2.2. You'll have to search for the thread though. I start with an item's rarity and then move your chance to acquire it based on its importance to that individual. You must then roll a test of PERSUASION to buy it at the stated price. My basic Task Difficulty Levels are...

Very Common Item = EASY (Skill X 2) test
Common Items = ROUTINE (1.5 X Skill) test
Uncommon Items = AVERAGE (Skill) test
Scarce Items = DIFFICULT (Skill X 0.5) test
Rare Items = FORMIDABLE (Skill X 0.25) test
Extremely Rare/Experimental = IMPOSSIBLE (0.1 X Skill) task

An Outstanding Success (rolling under RAW Skill without Attribute on an Average task) will get you a 10+1D20% Discount.

An Exceptional Success (rolling under HALF your RAW Skill without Attribute on an Average test) will get you a 50% reduction in price.

Rolling OVER your needed score but under your RAW Skill (the 1-10 number) will cost you 10+1D20% more.

Rolling over your entire Asset (your Skill + Attribute) will double the price.


Also, please note that this is just for buying things or doing "horse trading/bartering" during play. FINDING what you need is a roll on your SCROUNGING skill.
I allow anyone with Economics to add a bonus to their roll.