Until recently, I had every job listed and amount paid going back to 1991. They were stuck in the basck of a garage that needed a clearout. When clearing out, I decided to only keep the stuff from this century. So I have full details going back a decade. Each year, I will shred another years worth - though the computer records will remain as they take up no space worth bothering about. Within that paperwork is a photocopy of every cheque I have banked since I started scanning them a few years ago (6 per A4 sheet).
I believe that you need to keep details for seven years (six plus the one being worked currently). It doesn't take up much room for me. Just one decent sized box per year. In fact, until I started photocopying cheques, I could comfortably fit one year into a standard A4 box file.
Bear in mind to keep the bank statements too and also the credit card ones if they may prove relevant.