[Koha] Foolproof backup suggestions

[clint.deckard]

I am donating a server with Koha 3.12 on Debian 7 via packages for a 
school in Vanuatu and would like suggestions for a simple backup strategy.
The 'server' will not actually be network connected, so it will be used 
as a standalone workstation (at least to begin with). There will be no 
technical support available.
My first thought was to use koha-run-backups and change the location to 
the desktop of the user that will access Koha. With the thought they 
could drag and drop the backup folder to a usb drive when needed. But it 
appears the --location: argument does not work with koha-run-backups.

Since I am a novice scripter I am reluctant to go this path for fear of 
making a mess that I can't fix from thousands of KMs away.

I doubt the machine will run 24/7.
Any suggestions would be gratefully received.

A little of the backstory:
http://www.edgazette.govt.nz/Articles/Article.aspx?ArticleId=8749

many thanks,
Clint.