As of now, it costs 100 to marry and 1k to divorce. It is very cheap, that you can afford it right after doing the tutorial, and it doesn't really do anything more than allowing summons.
In my opinion, there are much more features that can be added to this.
One idea is a limited linked inventory that both of the married players can have access to add and use items stored. Of course, players are required to pay for each item to be added to the inventory, and there are limits the items you can add (you cannot add 2p mounts or other extremely valuable items) to prevent abuse. Of course, If such features are added, marriage and divorce should cost a lot more, so people will not just be marrying someone and divorcing them the next day.
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