Hi there, you should think of your solution as a SaaS, or to be displayed as iFrame on clients website/app that runs on your bubble app as a platform where a client uploads all the content outside his platform, where the client subscribes for a gadget or service on your platform and where client related content and updates are pushed to all clients accordingly.

I have also previous experience with a huge client a startup from Dubai within Travel and Tourism and back-end development on Bubble and XANO, and a lot of integrations in-between.