I am no techie, but what about using a decentralized cloud storage for this?
For example SIA?
some takeaways from what they offer:
Sia encrypts and distributes your files across a decentralized network. You control your private encryption keys and you own your data. No outside company or third party can access or control your files, unlike traditional cloud storage providers.
Far More Affordable
On average, Sia's decentralized cloud storage costs 90% less than incumbent cloud storage providers. Storing 1TB of files on Sia costs about $1-2 per month, compared with $23 on Amazon S3.
Sia distributes and stores redundant file segments on nodes across the globe, eliminating any single point of failure and ensuring uptime that rivals traditional cloud storage providers.
Sia’s software is completely open source, with contributions from leading software engineers and a thriving community of developers building innovative applications on the Sia API.