I am sure that everybody already has made the nasty experience of erroneously selling precious parts of items in inventory. In some other multiuser game I have seen the possibility to mark items in inv as 'no sale'. RP-wise this can be thougt as some mark "personal property. not for sale" placed on the item so that any trader would politely refuse to take it. Technically, it shouldn't be too hard to implement such a feature as certain parts like start equipment etc. already have a non tradeable property. The only difference would be that the player herself may place and remove it.
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Daomei die Streunerin - religionsneutral, zivilisationsneutral, gildenneutral