That is a hard one to as there are a lot of fansite items around and the price depends mostly on the frequency that fansites organize quests.
I would say memory box is the cheapest around since it is the fansite item of TibiaEvents. We organize contests and events on a monthly basis so there is a new memory box around every month. Price ranges from 45 to 55kk
Latest contests that gave fansite itens were promoted by TibiaLife, giving a Adamant Shield and TibiaMagazine giving a Midnight Panther Doll . Both are for sale on Antica Trade Boards for around 200kk
Also for sale on Antica Trade Boards you can find Heavily Bound Book for 90kk, Epaminondas Doll for 55kk, Shield of Destiny for 110kk,
Few original fansite itens that are from fansites that left the program (for that reason you can buy a replica of the fansite item on Adventurer's Guild) can be find with prices around 50kk, such as: Doll of Durin the Almight , Friendship Amulet , Draken Doll , etc.
For most of regular fansite itens I would say that the price ranges from 100 to 150kk.
I have recently seen the prices of these items: 400KK, 60KK, 135KK,150KK,70KK,45KK,45KK,40KK,85KK,100KK,110KK,150-200KK,150-200KK
In my opinion price depends on what server you play. I don't know prices on non pvp serves but I know items there are cheaper. I have few fansite items so I can tell you price of my items. Crunor's Heart cost 300kk, panther doll 140kk, assassin doll 90kk, black knight doll 85kk, shield of destiny 80kk, music box 50kk, pigeon trophy 30kk, royal medal 20kk.
Not fansites, but only contests items: 60-90kk & 60-90kk & 20-40kk & 20-30kk, 10-30kk.
based on own knowledge and trade world antica.
Recently I've seen The Epic Wisdom on EU non-PvP for 130kk.
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