What are the regulations and etiquette for a conversation and proposal for a girl whom a young man wishes to marry, and what questions is he permitted to ask her or her family before or during the proposal?

The default rule concerning a man's address to a non-mahram woman is that it should be limited to what is necessary, from behind a screen, without a soft voice, and without seclusion. This is based on the Almighty's saying: "So do not be soft in speech [to men], lest he in whose heart is disease should covet, but speak with appropriate words," and the Prophet's (peace be upon him) saying: "No man should seclude himself with a woman unless she is accompanied by a mahram."

If these regulations are observed, it is permissible to ask the girl about her guardian and her home address for the purpose of engagement, and to ask her opinion about marrying him. There is no specific ruling on who are the best people to accompany the suitor, but consulting people of virtue and righteousness is closer to achieving the goal. There are no specific topics to discuss during the engagement except those related to the dowry and conditions.