The easiest offsite backup would be any cloud platform. Downside is that you aren’t gonna own your own data like if you deployed your own system.

Next option is an external SSD that you leave at your work desk and take home once a week or so to update.

The most robust solution would be to find a friend or relative willing to let you set up a server in their house. Might need to cover part of their electric bill if your machine is hungry.