As all correct answers: it depends on what you with your data.
Do you need instant access to that DATA? Can you wait a big download to use it?
I'll assume you want everything as close to you as possible, and you want backups.
I am not familiar with a ReadyNAS, but Synology has a feature in which you can have two NAS at different places and they can automatically sync between themselves. This would allow you to have a NAS at home with ~8TB and another at work. This might cost you over 800$ including drives. You can also install a dropbox-like client if you want some folders on your local computer (you don't want all that store local. if you do, you don't need a second NAS at the office).
If your data Is important, I would create a AWS Glacier, Backblaze or equivalent write-only cloud storage for backups, There are expensive for the first transfer, but after the initial sync they become cheap. It only becomes expensive again if both your house and office burn down and you need to retrieve your data from them.