PHP Web-Based ERP Development -- 2

I’m looking for a developer to turn my working prototype (try it here: https://7star.abujawaid.com/login.php ‑ user: admin | pass: admin123) into a robust, production-ready ERP accounts system written in PHP and fully responsive for phones, tablets and desktop... (Budget: $15 - $25 USD, Jobs: Backend Development, Bootstrap, C# Programming, MVC, MySQL, PHP, Python, Software Architecture, Website Design)