Who has the right to decide the amount of mahr to be given by the husband to his wife? How much is the mahr supposed to be? Is a marriage valid without it?

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Check below answers in case you are looking for other related questions:
The marriage contract was done without any mention of the mahr (dowry)
What is the minimum amount of mahr? What is the modern equivalent of the mahr of the Mothers of the Believers?

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Related Answers:
Reducing the mahr is the Sunnah
Divorce before consummation is final and irrevocable
He did the marriage contract with her but she does not have any accommodation and he wants to be intimate with her
The marriage contract was done without any mention of the mahr (dowry)
What is the minimum amount of mahr? What is the modern equivalent of the mahr of the Mothers of the Believers?

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