You need to test this, I used to do the same and took just my external drive to my parents home one day. I found out their microsoft works could not open my microsoft word or excel documents and the microsoft money, access and publicher are even worse because you have to have the same version. So I made some changes such as switching to open source software that can also run from the drive (portableapps.com) so I didn't need any install cd's and when I was shopping for a new computer bought the smallest lightest laptop I cold afford (at 3.5lbs its not much more heavy than an external drive). With the laptop if I need to bug out I take it and can start working in any place I stop at be it my bug out location or hotel without needing to find something to plug my drive in to. I actually have an old HP portable printer in my long term gear for if I would need that now as well, I picked it up for $5.

I also stopped using safe deposit boxes after seeing NOLA figuring any near enough to me would suffer from the same disaster that forced me to bug out so I have my important documents stored at my bug out location.