I back up new purchases every time I unzip them to an EHD. Downloaded photos as well. I have another EHD that does a back up twice a week of my important folders. Then I have 2 additional EHD's that have full backups on them. I do those monthly (well, I do try). One is a really old EHD that needs to be plugged in so I'm taking it out of the rotation and this weekend I'm setting up a new EHD backup on a much bigger EHD. I used to have Backblaze but when it was disrupting my internet connection, it got to be a pain. Nothing like having your internet connection drop while doing something. And, when that computer was zapped during a power outage due to a tornado in the area, I found that when I didn't have BB running, my internet connection never dropped. Even after getting a new computer if BB was running, I had internet drops. When it wasn't, no drops. So I dropped BB and haven't had any connectivity issues since! But I will say for many years, it worked great. It was just the last 2 to 3 years that I had problems (and I blamed them on my local ISP).