Manual meter Thread best practices

I want to start a thread to gather some good implementation on how to store and present meter data (Power, gas).
There are good guides for making a manual meter smart.
But in some cases one cannot or doesn’t want to.
I am currently still using an Android App called Ecas,
which offers multiple meter incl conversions and timestamp that offers nice reports.
My personal Goal would be to move this to The Home Assistant Dashboard to have all in one place.
I will also add other topics that fit.
Looking forward to read from your experiences.