Maybe even a special event in era, for 1 day only you can sell unwanted items for 25% of the price you payed for it, this would give alot of players the chance to sell their unwanted items but for a low price, the catch could be that there is a limit to items that you can sell maybe like 5-6 or maybe a little less, this is very reasonable to me because instead of having a place to sell items 24/7 theres only a 1 day event.