Who is her wali and how do I propose?

Selamu Aleykum, I apologize for the long question but I have many which I cannot find answers to, I would greatly appreciate your help! I am Turkish living in the US, living in an area with next to no muslims at the moment (we only have a small mesjid and all the women are married), and plan to propose to a pious Christian girl I know,� named H.� We have both spoken to each other about it and agree we are a good fit; elhamdulillah she is chaste, she respects Islam very much and has promised we will raise the children Muslim. The first issue is in finding her Wali.� Her father unfortunately passed away two years ago, and she has no surviving paternal male relatives that know her well enough to represent her, she only has sisters, and her mother has two brothers she knows *at all* but I have read maternal relatives cannot represent her.� I have also read that in our Fiqh, the woman does not need a Wali to represent her, which may solve the problem but I don't know how accurate that information is. The second issue is in the proposal itself.� First, Is it Sunnah to recite Khutbat Al-Hajaah when I propose or only at the marriage ceremony?� Second, I feel I should�ask�her mother, as her parent even though she is not a Wali.� Is this necessary and should I�ask�her and the Wali together with H or can I�ask�them separately before, and�ask�H after I get their permission?� Third, in my country we give lots of nice gifts as the mahr, which I would like to do, but I have read that you don't give a mahr to a kitabi in some fiqhs, what is our fiqh's position on this? Finally are there any other sunnets or requirements I am missing? Thank you so much for your help, barakallah