Without the specific quests that you have already done I am afraid I can't give you a price.
From this list, what quests have you already done:
Cook's Assistant
Fishing Contest
Goblin Diplomacy
Big Chompy Bird Hunting
Biohazard
Plague City
Murder Mystery
Nature Spirit
Priest in Peril
The Restless Ghost
Witch's House
Gertrude's Cat
Shadow of the Storm
Demon Slayer
The Golem
The Lost City
started Legends' Quest
Family Crest
Heroes' Quest
Shield of Arrav
Lost City
Merlin's Crystal
Dragon Slayer
Druidic Ritual
Shilo Village
Jungle Potion
Underground Pass
Biohazard
Plague City
Waterfall Quest
Monkey Madness
The Grand Tree
Tree Gnome Village
Desert Treasure
The Digsite
Temple of Ikov
The Tourist Trap
Troll Stronghold
Death Plateau
Horror from the Deep
Barcrawl miniquest