C# Solution to Retrieve Phone Numbers with reCAPTCHA v3

We are looking for an experienced C# developer to create a solution for retrieving phone numbers from a website. The process involves bypassing a reCAPTCHA v3 challenge using an external tool (API key provided). The implementation should not rely on external browsers (headless or otherwise).

Project Details:

1. Objective:
Retrieve a phone number from a website using C# by solving reCAPTCHA v3 challenges programmatically.

2. Workflow:
- Extract the listing ID from the page source.
- Solve the reCAPTCHA v3 challenge using an external tool (API key and documentation will be provided).
- Send a request with the solved reCAPTCHA token and listing ID to retrieve the phone number.

3. Requirements:
- Use C# as the programming language.
- No external browsers or UI-based automation (e.g., Selenium, Puppeteer).
- Integrate with the external reCAPTCHA v3 solving tool via its API.
- Ensure clean and maintainable code with proper error handling.

4. Deliverables:
- A fully functional C# project that fulfills the outlined workflow.
- Clear instructions on how to use the solution, including setting up the external API for solving reCAPTCHA.

5. Qualifications:
- Strong knowledge of C# and HTTP requests.
- Experience with API integrations and handling reCAPTCHA challenges.
- Familiarity with extracting data from website page sources.

6. Additional Notes:
- The external reCAPTCHA solving tool and API key will be provided to the selected developer.
- Please ensure that the solution adheres to best practices and avoids unnecessary complexity.

To Apply:
Submit your proposal detailing your relevant experience and estimated time for completion. If you’ve worked on similar projects, feel free to share examples.

Looking forward to working with a skilled developer!