If your broadband supplier limits your upload to something silly like 30Gb in one month why not limit what files you upload, for most small business I use the following exceptions
To input excptions, click on backblaze icon in bottom right hand corner of screen and go into settings then exceptions and input the list above, you also might want to take a look at excluding
jpg = images
pst = emails files (very large files and if you change one bit in them they have to re-upload) best get your hosting company to backup your emails.
aud = Audacity creations files, normaly lots of them and not needed.
All these exceptions are specific to different people so if you have any questions please contact me.
There is also option ot exclude more folders depending on what you want do My videos and My pictures could also just be put in as a blanket rule.