The only thing you also need to be aware of is that you want a backup of that backup--preferably off-site; something like Backblaze, CrashPlan, OneDrive, Dropbox, or SugarSync.

Another idea would be something like the WD My Cloud device to perform a local backup (which can be scheduled to be performed automatically). Then get an Office 365 family subscription for $100/yr. That will give you unlimited storage on OneDrive--which you can set to automagically backup everything on your laptops.