[Mostrous Eyes] strange trader prices

I've been wondering for quite some time now why the behaviour of the trader is like this:

When you see an eye in the list of available items, it shows for 100g, but when you actually buy it it switches to 200g. I know this can happen when the price changes after the last sale, but this has been the case for months now.

Any clues?

I have no idea why but I've noticed the same thing with superior runes.

The sale value of the items has to be doubled for the buy value from the npc sellers.

sale value=100g buy price= 200g minimum

Even better example of this wrong display of prices is the Rare Scroll Trader. He shows the prices which the items should have based on how many were sold/bought from him (sort of supply/demand price determining system) but also has a minimum buy and sell prices set.

they're scammers!!

As Bane of Worlds explained, its double the merchant value for any item that sells at base value.
This is done intentionally, just as bones are always 100g at the trader even though they only cost 30g at the merchant. It is done to drain money out of the economy.

It is also meant to prevent fast selling (ala 1920s stock market). If you buy monsters eyes at 100g each (their merchant value), you can just hold them and wait till they rise a little bit in value to 110g and then sell them all and make a lot of profit. If they don't rise in value, then you can just sell them back to the trader or the merchant at 100g each and thus lose no money.

Basically, that creates a no risk investment that is guaranteed to at least break even. Very bad for the economy.

However, by doubling the merchant price that you can buy them at to 200g, it makes investing in materials more speculative. If somebody wanted to buy 2000 monstrous eyes, he's going to think twice about it now because he could lose a lot of money if they don't increase in value significantly.

Thank you for this. Learn something new everyday.

How come this has never been the case with ectos? Why are they only 1-1.5k lower instead of doubled? Is it because they are used as currency?

I don't think hes talking about the current value at trader, but the actual value that you could sell to the merchant at anytime.

They have minimums, ecto is well above it. Any other trader item that goes above the minimum will get the same treatment. There are both minimum sale and minimum purchase prices.

You can identify runes and, like any other object, this increases it's value to the merchant. It isn't unusual to have a superior rune identify at 60-80 gold. If it is a rune that the trader is at it's minimum already it will go for the identified price, not just the 25 gold unidentified minimum. I found that to be amusing as well (my guess is that the trader compares it's current price calculated by supply and demand to the value inherent in the object and gives you whichever is more).