I feel your pain. Life seems to get more completed over time, especially when you’re managing properties, businesses, etc.
I scan everything with ScannerPro on my iPhone (which OCRs text to make it searchable) as items come in via mail etc. or print to PDF if I see myself needing something later. Scanned docs sync to Dropbox, and I move them to their appropriate Dropbox folder (e.g. property, taxes by year, biz, etc.) when I sit down at my laptop. It’s worked pretty well. I think the key is focus on the new docs, and you’ll eventually stop needing to refer to the old paper docs in your old folders (rather than trying to scan literally everything, which seems like a daunting task).
I scan everything with ScannerPro on my iPhone (which OCRs text to make it searchable) as items come in via mail etc. or print to PDF if I see myself needing something later. Scanned docs sync to Dropbox, and I move them to their appropriate Dropbox folder (e.g. property, taxes by year, biz, etc.) when I sit down at my laptop. It’s worked pretty well. I think the key is focus on the new docs, and you’ll eventually stop needing to refer to the old paper docs in your old folders (rather than trying to scan literally everything, which seems like a daunting task).