Dear Employer,
We have an experience with Zappier.
We can do the following:
1. Separate integration flows with web hooks
2. Integrated Node.js solution using Zappier interface (it is usually what Zappier recommends as a vendor)
The job is not trivial as some components you listed do not necessarily have ready Zappier interface.
I would suggest to run the job in two phases, the first to understand what you need and propose the design - at a total of $200, and later on at an hourly rate we will deliver agreed upon solution and milestones.
Recommendations are available upon request, and my prior employers included BoA, DIsney and other companies of different sizes and reach.
I specialize in integration and love doing such projects.
Sincerely, Virginia