1. I do need the support to implement the legalization part (I don't know how to run c-corp or something)

2. For free? What is the profit for them?

4. Suddenly not, I rely on 3rd party providers and they cost me some money.

The problem is that I can't edit post right now. So here is the link: https://goandcall.me (I've got very bad communication and copywriting skills but I promise I will improve them).

The main idea that you can get a link or widget for your website, email signature or get it per prospect via API. This link will help your customers call you without any plugin or additional software. Free for customers, paid for you. You can manage links and numbers (activate, deactivate, assign schedule).