Another lawyer here. I cosign everything @rescuedrelics said.

I understand the frustration you have with paying to the sync service. I have had the Remarkable for about a month and do not use the sync service, even though it is free for an intro period. The way I look at the device is as an exact replacement for a paper legal pad. I take notes and use the rM app to export to Dropbox or Onedrive on my computer. If you do that, you can’t really update the notes, which are saved as a PDF. But, I could not really do that with paper notes.

If I am working on a research project and know I will be adding or editing the notebook, I just leave it on the rM until it makes sense to save a copy.

Maybe that will work for you.