implement stripe payments for a saas product

What we need;

- fully implement stripe into an existing SaaS product
- Products must pull content/products directly from Stripe production
- 3-day trial for each product to be set in Stripe
- Code changes/updates commented and committed to GitHub repo
- Current product upgrade - ability for a user to upgrade or change their current product
- no hard-coding products, they must be pulled from stripe
- all remaining functionality of the current app must work as per current standard working ability.