Backend Developer needed to build Investment Platform Logic with Braintree API, other APIs & CMS

We are currently building a platform where you can collectively buy collectibles (in the form of Assets) such as Pokemon Cards, luxury watches, or hyped Sneakers. The user buys shares in those unique assets and participates in their performance. You can collectively agree to sell the product or individuals can trade their shares within the Platform. Collectibles are an alternative investment, which means they're not stocks, bonds, real estate, or cash and are not considered.

Tech Stack:
- Node.js + Strapi Headless CMS // also open for different CMS & Backend Tech Stack
- React / Next.js (already in use & finished)
- Braintree Payment API https://developer.paypal.com/braintree/docs/guides/braintree-marketplace/overview
- Concedus API (https://documenter.getpostman.com/view/9924789/UVkjvHCm#intro)
- IDNow KYC API (https://docs-autoident.idnow.io/?version=latest#107f6d04-34a7-4ac7-a8b4-e0243b9f4450)
+ Open to any addition (for example firebase) that makes this Project easier and faster to complete, even open for finished Backend Solutions that we can adjust.

Backend Logic Planning: https://www.figma.com/file/nM4faampNrKNQWWue51Nh9/Xenleo-Backend-Logic-Planning-(share)?node-id=0%3A1
- Single Data Types all refer to CMS possibilities
- Collection Data Types are both CMS possibilities as well as features that are part of the regular Backend Logic
- In the Payment & ownership Flow you see how the Payments behave on the platform

Features:
- All of the features are described in the Collection Data Types available in the link above (read through it and you will have a deep understanding of what's needed).

The Frontend is completely finished. We need the Backend Logic built and integrated.

DEADLINE: The full backend needs to be finished and integrated within the next 1 to 2 Months!

Thanks.