I too recently replaced my old alarm panel and the keypads using the existing wires to power everything. I’m not taking credit for this approach (followed other’s examples here) - but it worked nicely. Fortunately, there was a single gang electrical box behind each keypad - for which the USB adapter fits in nicely.
For the keypads: I bought (1) USB adapter for each keypad: https://www.amazon.com/gp/product/B07RDGR9GF/ref=ppx_yo_dt_b_asin_title_o09_s01?ie=UTF8&psc=1
Then I purchased (1) wall transformer to power both keypads:
https://www.amazon.com/gp/product/B002IS1UW4/ref=ppx_yo_dt_b_asin_title_o09_s00?ie=UTF8&psc=1
This allows me to keep both of my keypads powered from the basement.
In addition, I ended up wall mounting my Ring Panel in the same location that I had a “siren”, and using the existing siren cable to power Ring Panel from the basement, with these adapters:
https://www.amazon.com/gp/product/B081TV7SQ7/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1
https://www.amazon.com/gp/product/B07C61434H/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1
Hope this helps!