There is no doubt that mahr(dower) is one of the woman’s most important rights; however, it has to be given according to the social and financial status of the husband. Therefore, Islam did not define a fixed amount of dower and subjected it to the agreement of both the woman’s guardian and the bridegroom. Moreover, Islam encourages the dower to be reasonable and not expensive.

The Prophet (peace and blessings be upon him) said, “The best woman is the one whose mahr is the easiest to pay.” (al-Haythami)

The Prophet (peace and blessings be upon him) himself never asked for a huge amount of dower for his daughters, so parents and guardians have to follow his example and be humble when they give their daughters in marriage. They have to concentrate on the religious commitment of the bridegroom.

In his response to your question, Dr. Main K. Al-Qudah stated:

What is expected of parents nowadays is to facilitate marriage for their children, and to make this happen with the minimum possible cost.
It is unfortunate that some parents- unintentionally- contribute in the spread of immorality in society by complicating the marriage issue for their children. They make it really difficult and unaffordable for the Muslim youth who are looking for chastity and protection against fornication through marriage.
I advise Muslim youths to keep searching for practicing and committed parents who understand their situations, and who recognize the fact that marrying their daughters to them is not a business transaction. Rather, it is an application of the Sunnah of the Prophet
(peace and blessings be upon him)
and a great contribution to the morality, chastity, and modesty of the whole society.
At the same time, and according to the advice of the Prophet (peace and blessings be upon him)
himself; fasting is a protection for those who can not afford marriage.
May Almighty Allah ease our affairs and make us adhere to His religion.