Looking for SMS Verification / Receive SMS Platform Script (Template or Ready-Made)

I’m looking to build a web-based SMS verification / receive SMS platform and would like to know if this is something you can help with.

The platform functionality should be similar to:
- onlinesim
- smspva
- 5sim

Main requirements:
- Backend-focused web platform
- Integration with third-party SMS verification APIs
- Users can request temporary phone numbers and receive verification codes automatically
- Admin dashboard for system and user management
- REST API support (preferred)

This project is for legitimate SMS verification and testing purposes only.

Please let me know:
1. If you have experience building similar API-based platforms
2. What tech stack you usually use
3. Estimated cost and delivery time

If available, please also share:
- Previous cases or related experience
- Demo URL

I’m looking for a long-term partner. If the cooperation goes well, I’m open to ongoing and long-term collaboration.

Thank you.