I use backblaze on my synology. I backup photos automatically to it with their built in app on my phone, then every night I run encryped backups. I also could setup an encrypted backup to go to my parent’s synology.
My backup is about 900gb and costs <$5/mo. That is my music, pictures, movies, and TV shows. Obviously that will increase, but well worth the nominal coat to have that much backup encrypted and in the cloud.
SeeJayEmm