You need to stop limiting the amount of items, I've said this more then once, but honestly if you limit the items to a certain amount that just makes us want to buy that specific item from whoever has one, and once we have them all we destroy all but one which increases the value of it.
Then you're left with no choice but to put some more into the economy and that will just make the guy who bought them all and destroyed them really really mad. You need to have an unlimited amount of nearly everything.
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To obtain something you must sacrifice something of an equal value.