Does the Istikhara prayer obviate the need to inquire about and investigate an unknown suitor, especially if that is difficult and he has proposed alone with certain justifications?

A long marital life requires careful consideration in choosing a partner. Selecting someone with good religious commitment and character is one of the most important reasons for its continuation. While istikhara (seeking guidance from Allah) combines all goodness, consultation is also necessary. Therefore, strive to ascertain the young man's character. If you are predominantly confident in his righteousness, then accept him. Otherwise, it is better to decline.