But for a household -- there are very few documents you need to keep long term. Better to just keep those in a fireproof file box, and shred and discard everything else rather than devote any resources or mental energy to keeping them around in either paper or digital form.
I disagree. While I'm a huge fan of purging, there are many, many cases where you need/want documents.
Theft/fire/casualty: old receipts prove ownership and value.
Maintenance: who worked on the furnace 4 yrs ago?
Warranty: our windows have a 20 year warranty (and we're using it!)
Basis for home improvements: when you sell your home, if you can document improvements, you can raise your basis and lower your capital gains.
Repair: where's the part number & diagram for the faucet that's leaking?
School records for your children.
Etc.
But I was really more thinking about everyday utility bills, other statements and invoices -- I just trash all that stuff as soon as it's paid. I have better things to do than organize papers that I will never look at again.
All other items are either delivered electronically, like bills, or scanned and shredded upon arrival, like insurance policies. (Sometimes I take a picture of manual covers or packaging so I can have part and serial numbers.) I keep copies of the files in various encrypted places, including a USB stick that goes with me.