Couple document questions for visa

Hiya, really hoping someone can help me.

I'm British and my Australian partner is applying to join me here. The financial requirement isn't applicable since I'm a carer for my mum, so I'm wondering which documents I would need to prove this for the visa application.

Also, we'll be engaged to marry, meaning we need to get married within 6 months of her arriving here. Would I need to prove intent to marry or anything? And how would I go about doing that?

I did call UKVI and the guy said he can't answer my questions because they are on the behalf of my partner. Although I've called them up plenty of times before and it was fine. Even more silly considering that the questions are for things that I myself would need to provide...

Thank you for reading, here's hoping you fantastic people can help

See Appendix 2 part 4 https://www.gov.uk/government/uploads/s ... endix2.pdf
and Guide to Supporting Documents
https://www.gov.uk/government/uploads/s ... lement.pdf

Regarding evidence of the intention to marry, although you won't be able to register a date you can contact the registrar and ask for confirmation in email or in writing that you have approached them for information on arranging a date for the wedding. You could also submit quotes from venues, caterers etc.