yellowroom

Glad to be of help - I went on a massive scanning and shredding binge when I repatriated, albeit in better circumstances than you. I would encourage use of online storage rather than rely on an SD card alone - SD cards can easily be lost during a move, and then all your information could be picked up and accessed by the card finder. Whereas services such as Dropbox, Google Docs, Apple iCloud etc are quite secure, especially if you have two-step security (eg your password and a code sent to your phone or email address, but be wary of relying on a US phone number if you are moving back to the UK).

I had copies of key documents (eg passport, birth certificate, visa etc) stored on a password protected USB stick on my key-ring as well as my Dropbox copies. Whatever works for you, just make sure you have back-ups and don't rely on one location for storage.