Custom Client Dashboard Development

I'm seeking an experienced developer to create a custom client dashboard similar to WHMCS. The dashboard needs to include:

- Client account management
- Automated billing and invoicing
- Support ticketing system

The dashboard should also integrate with the following payment gateways:
- PayPal
- Crypto

User roles required:
- Admin
- Client/User
- Support Staff

Ideal skills and experience:
- Proven experience in developing similar dashboards
- Expertise in payment gateway integration
- Strong understanding of user role management and security
- Proficiency in backend and frontend development

Please provide examples of similar work done and your approach to this project.