Freelance Coding Project – SaaS payment implementation (Python/Django/JS)

Can you code a payment solution for this Google Chrome Extension?
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This video shows the main features: English version
German version
Currently, it's freeware but soon it should be trialware. After the trial period, users will have to buy a subscription license to continue using the product. I didn't pick a Payments Service Provider yet, but I already decided that I want many payment options like PayPal, Google Pay, Apple Pay, Credit Card, etc..
The Extension uses a cloud server (Django/Python) to sync the project lists. So the backend is already working fine.

Your role would be to code access control dependening from the payment status.

Project details

For the user the process will be like this:

1. User signs up here: www.hideseenhits.com/sign-up using their email and a password only

TODO
• nothing (already implemented)

2. Trial period of 14 days starts – they can use the extension normally
TODO
• Backend: create new database column "trial end time (JJJJ-MM-DD.mm.ss)"

3. After 14 days the extension's GUI shows a link "Trial period over. Please choose a plan here!" leading to www.hideseenhits.com/plans
All GUI elements necessary for proper use get hidden (Project lists, Hide-buttons ["hide all" and "hide globally"])

TODO
• Extension Frontend: create periodical check (every 10 s) for license status
• Extension Frontend: if user is not signed in, trial period is over or license expired mentioned elements get hidden

4. (First page) Showing plans of 1, 3, 6 or 12 months. Just the price differs – same features of all. Clicking a plan leads to next page
TODO
• Website Frontend: create page in HTML/CSS (my job)
• Website Frontend: implement API of subscription billing software provider (Pabbly, Chargebee, Chargify, ...)

5. (2nd page) Order form. Inputs
• Email (automatically filled through handover buy extension)
• First name
• Second name
• Street incl number
• Post code
• Tax ID (if applicable)
• Payment method

TODO
• Website Frontend: Create HTML template (my job)
• Website Frontend: implement API of subscription billing software provider

6. (3rd page) Payment
TODO
• not much I guess: page delivered by Payment Service Provider such as PayPal

7. (4th page)
Text "Your account has been reactivated. Enjoy HideSeenHits"
The extension's GUI re-shows all elements that were hidden before (Project lists, Hide-buttons ["hide all" and hide "globally"])

TODO
• Website Frontend: Design HTML/CSS (my job)
• Backend: update license status to Django database

Contact me if you're interested in this project.
Thanks, Max
ms@maxschwarz.de