This.

And, somebody suggested that Era introduce a pawn shop of some sort...where players could sell back their items to an NPC for a percentage of what they paid for it. Which would create a minimum sale value...

You give the players the ability to price items, but you still set the price roughly by controlling what they need to produce it, how much it costs, how much of it they need, and its availability.

You make valid points, though. But more often than not players are going to turn profit, so I don't see them selling an item for very much less than they bought it, especially when limited supply and/due to high production cost is a factor.

Yes this would fix the problem and make the economy a lot more stable.
Pawn shop would make a minimum sale value and the shops selling the guns would set a maximum sale value.

Every single gun would need to be sold in a store though.

Not necessarily...as much as I think stabilizing the economy is important, I also think it's important to introduce some items with rarity. Having rare items to shoot for gives players another reason to play. How those rare items are introduced sometimes can become another economic problem, though (such as the WWII guns).

I suggested a long time ago that we create a big incinerator or crusher or whatever at the junkyard, where people could get a little bit of money for old guns or cars.

Something...anything...to create a minimum sale value, so prices don't continue to drop so much.

Once people stop buying the item in stores because they can get it cheaper from players, there are no taxes flushing money out of the economy. If people don't buy it from the store, obviously money is not being taken out. Buying from players, you're just shifting the possession of the money. Nothing is being taken out.

How can players make profit on a 50k item when players can just buy it in the store for 50k? You're not going to sell it for any more than 50k.

Now all you're doing is making a select few players rich. They buy a gun that was only stocked 3 times for lets say 50k. The demand is really high for the weapon, so they can go and sell it for 100k and make profit. Dumb idea.

Huh? Explain a bit more ;o

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Overall, completely limiting businesses is a bad idea. You might as well avoid the whole situation and just not bother with player owned businesses. It causes too much problems.

See? Now this is why Blizzard made all rare and above equippable items locked to that character once equipped. Which if I may add, is the best solution in all cases.

we had a kid selling his account with an undroppable weapon he won in an event before, lol. not saying everyone is going to do that, but it's not the best solution.

The actual supplies used to craft the items. Like for a gun, you can use a certain gun part thats sold by an npc owned shop. You edit the stock and pricing to suit the economic needs. If production of an item is booming undesirably, you can either limit the available amount of key materials needed to make that item, or just simply make them more expensive. The value of items drop when there are tons of them floating around, and these simple measures can completely prevent/fix that.

By changing what is needed to craft items in shops (their availability and price) you indirectly influence the retail price. If something costs $200 in parts to produce, no one is going to sell for less than that. It's also another way of assuring the shop owners don't walk away with millions.