The best way to make carbon copies of your files is to use file sync software designed for it. I’ve only used two or three services but there are plenty more to choose from. I’ve also used software not tied to any service.
I received the least amount of free storage space from Dropbox when I signed up years ago but it’s the service I’m using today. My database backups are uploaded daily using a BASH script.
I’m only listing the services that offer free storage space (and know about). As far as upgrades go, I’m only listing the least expensive option. Most have multiple options. I’ll add more services as I discover them.
All of these services offer more upgrades than what I’ve noted. Some of them offer additional services as well.
The only file sync services I know I have accounts with are Dropbox, Google Drive and Microsoft OneDrive. Google Drive comes with my email account and Microsoft OneDrive came with Windows 8 (when it was still called SkyDrive).
There are file sync software products not tied to any service. I can only list those I know about. I’ll add more products as I discover them.
If you have the programming knowledge, or know someone who does, you can set up backups to external devices at regular intervals. With USB flash drives and SD cards getting bigger than most internal hard drives, it could make sense to ignore everything else.
A synchronized file is nothing more than an up-to-date backup. While online backup services and file sync software may be more convenient, they can still malfunction and you can still lose valuable data.
This wouldn’t be too hard to set up for a home computer but it would be difficult to do it from a web server to a home computer without an intermediary. I think I would still use Dropbox and then backup the local folder to another device.