I'm about to have "the talk" with my aging parents - what do you wish you had known before you started helping your retirement-aged parents with their finances?

I'm in my mid-30s and am witnessing a lot of my friends starting to help their older parents with financial messes (getting into assisted living facilities, uncovering unpaid taxes, etc.) and while my parents are still healthy and independent, I want to learn more about their finances so that I can be more informed when a stressful situation does come up down the road.

What I already know - from reading this sub, I know what info I need to collect (credit history, account info, names of lawyers and accountants, etc.).

What I don't know - what are some things that they could start doing now to better position themselves in the future, should they need to move into assisted living or longer-term care facilities, that will cause less stressful paperwork during a time where they just need care / medical attention?

EDIT: I am not trying to take over managing their expenses. They are doing that just fine. I just want to know more about their finances so that I'm not digging through papers in the basement when they may have a medical emergency and I'm trying to get them the care they need.

Any other tips you wish you knew before you had to step in to help your parents? Thanks in advance!