How accurate is the statement that seeking forgiveness 73 times daily for forty days, then waiting three days, leads to marriage?

Persevering in seeking forgiveness (Istighfar) is a cause for relief from distress, in affirmation of the Prophet's (peace and blessings be upon him) saying: "Whoever adheres to seeking forgiveness, Allah will make for him a way out of every difficulty, and relief from every worry, and will provide for him from where he does not expect." However, specifying a certain number for daily Istighfar and attaching a particular reward to it has no legal (Shar'i) evidence and falls under the category of Bid'ah Idhafiyyah (innovations by addition). Therefore, what you read about specifying a certain number is incorrect. For facilitating marriage or good matters in general, one must obey Allah, and adhere to seeking forgiveness without introducing a method not sanctioned by Islamic law, and supplicate during times when prayers are answered. Furthermore, there is no impediment for a woman to seek a suitable husband or to offer herself to a righteous man, provided there is safety from temptation, though it is preferable for one of her male relatives to handle this.