To what extent is it lawful for fathers to exaggerate dowries, and is it forbidden, especially if it leads young people to commit unlawful acts?

The prescribed approach to the mahr (dowry) is to lighten and facilitate it, following the guidance of the Prophet, peace and blessings be upon him, who said: "The best dowry is the easiest." The mahr for his wives was five hundred dirhams, and for his daughters, it was four hundred dirhams. Some scholars have recommended that the mahr should not exceed five hundred dirhams.