Anyone have recommendations for building a custom AI agent that lives behind a paywall?

I’m looking for the simplest solution that allows:

1. Training a model on my own content (courses, podcast archive, etc)

2. Paywalled access, ideally accepting both fiat and crypto

Everything I’ve explored so far requires landing pages, third-party integrations, or complex stacks that feel like overkill (and cost). I just want to get it live without duct-taping tools together.

Would love to hear what’s working for others. 🙏