I’m building a single, integrated application that lets my garment stores handle sales, stock and bar-codes without hopping between tools. At its heart is a full Billing module: I need a drag-and-drop invoice designer where I can drop in our logo, brand colours and choose which fields go where. During checkout the cashier should be able to scan a barcode—USB gun, Bluetooth scanner or even the mobile camera—and watch the system pull the item, auto-calculate price, discounts, GST or other taxes, then accept payment by Cash, UPI or Card. Once payment posts, the app must generate an invoice automatically (manual, milestone or scheduled runs are also fine) and offer a print-ready PDF. Real-time payment status, plus overdue reminders, keep us on top of receivables. The same barcode engine needs to let us create codes for new products and print labels on standard stationery. Every product sits in a central Inventory area where we record size, colour, brand and rate, track stock-in / stock-out, trigger low-stock alerts and split quantities per shop. Although I will start with a single location, the data structure must already support multiple branches with separate stock buckets and a central admin dashboard. For reporting, I expect daily sales, profit, stock, shop-wise performance and full outstanding/payment history, all exportable to Excel or PDF. An Admin login should control master data and see everything; Staff logins will be limited to their roles. Deliverables I need to approve: • Web or desktop application (state your stack) with Billing, Barcode Management and Inventory modules fully functional • Custom invoice designer working end-to-end, including print layout • Payment entry flow for Cash, UPI and Card, tied to automated invoice generation • Barcode generation/printing and scanning support (USB/Bluetooth scanner & mobile camera) • Stock management with low-stock alerts and branch segregation • Standard reports as specified, with export options • Role-based user management Please outline your proposed tech stack, estimated timeline and any prior work with POS or inventory systems when you respond.