This is basically what I do as well, as I just end up lost in a sea of paperwork otherwise. I am still trying to write down my process flow but basically there are:
- documents where the originals must be kept (e.g. related to tax returns) and where I need the content available electronically (rent statements from DH's rented property and also stuff from school, car's V5)
- as above but electronic copy not required (e.g. legal docs)
First category is scanned then filed or put on the fridge til needed, second category goes in the fire safe.
- documents where no scan is required but where the paper is at least temporarily useful (e.g. credit card statements or utility bills, where I already have an electronic version but the paper ones are useful for proof of address should the need arise).
These go straight into a 'rolling file' which I (in theory) prune every 3 months. I actually haven't because the folder's not full, but I will chuck this lot at the end of the year. If we had any paper bank statements these would be kept for tax return purposes for much longer.
- basically everything else. DH has a lot of hospital appointments, usual school paperwork, bills, insurance, manuals for things, yadda yadda.
Everything, everything goes into Evernote. This allows me, among other things, to run my house whilst out at work - I can get to my in-tray and filing cabinet on my work laptop, my tablet, my iPhone and from any other computer via the web interface. I regularly just take photos of stuff on my iPhone and whack it into Evernote, and I use Papyrus on my tablet so my handwritten notes are already electronic (if I do take notes by hand, Evernote has a handwritten note mode where it will scan in, remove shadows and try and decipher your handwriting for keywords as well).
One word of caution about filing paperwork - whether real or electronic. Don't invest too heavily in a complex filling system. The chances of you needing to find a bit of paper again should massively influence the amount of time spent crafting the place where it will live. Most things if you dump into a year file you could find again with 10 mins. With electronic stuff, you can just do a search on a keyword, should take minutes at most. So don't overthink the filing, dump it and move on. This should also make it easier to keep up with the volume there is to, you can probably automate much of it depending on how you scan.
Hope this helps - I honestly couldn't manage our complicated lives without being able to get to my stuff whilst outside the home.