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The quest rewards offered by the player remain on him as inaccessible items, until they are given to the quest taker or the quest itself is cancelled.
A player may only send as many players on a quest as he can afford to pay with the allotted prize, i.e. if he has an amount worth of two prizes for the same quest, then he may only send two players on that quest. Of course, the quest prize itself is set by the player, in advanced.
The player may refuse to send another requesting player on any specific quest. Also, the player may put a time limit on his quest.
A quest may be available to the player only if the social requirements are met. For example, if the player's race or character are unpopular with the quest giver's race or character, then the quest will simply not be available to that player.