Hadith.4401 - Imam Ali ibn Abi Talib عليه السلام said: "Indeed, the most deserving of conditions to be fulfilled are those by which you make lawful access to private parts."
The Muhammadan tradition regarding the dowry is five hundred dirhams. Therefore, whoever exceeds this tradition should be reverted to it. If a man gives his wife one dirham or more from the five hundred dirhams, and then consummates the marriage, she is entitled only to what she has already received before consummation.
Any amount that a woman stipulates as a debt upon her husband from her dowry remains obligatory for him to pay during his lifetime or after his death. However, it is preferable that the heirs do not demand what the woman did not claim during her lifetime, unless she had explicitly made it a debt upon her husband.
Whatever the husband gives her, and she accepts as her dowry before consummation, is considered her dowry.
The reason why the dowry of the Sunnah is set at five hundred dirhams is that Allah سبحانه وتعالى, the Exalted, has decreed upon Himself that if a believer recites one hundred takbirs (Allahu Akbar), one hundred tasbihs (Subhan Allah سبحانه وتعالى), one hundred tahlils (La ilaha illa Allah سبحانه وتعالى), one hundred tahmids (Alhamdulillah), and sends blessings upon the Prophet and his family (peace be upon them) one hundred times, then asks Allah سبحانه وتعالى to marry him to one of the women of Paradise, Allah سبحانه وتعالى will indeed grant him a heavenly spouse and make that the dowry.
Furthermore, if a man marries off his daughter, he is not entitled to consume her dowry.