PHP Web Billing App Development

I need a lightweight, browser-based billing system built with PHP, JavaScript, and a MySQL backend I can manage through phpMyAdmin. The app should handle one-time purchase billing only—no subscriptions or metered usage—so the primary feature I’m after is streamlined invoice generation... (Budget: ₹1500 - ₹12500 INR, Jobs: CSS, HTML, JavaScript, MySQL, PHP, phpMyAdmin, Web Development)