HMC Billing System — AI-Powered GST Billing Platform

Hirani Marketing Combines, a Chennai-based trading company, was running its entire billing operation through Excel — manually re-typing customer and product details, calculating CGST/SGST by hand, and cross-checking stock across separate sheets. Mistakes crept in, invoices took too long, and there was no single source of truth for what had been quoted, invoiced, or paid.

At the core of the platform is a workflow that mirrors how a sale actually progresses: quotation → proforma invoice → final GST tax invoice. Each stage migrates to the next with one click — no re-entry, no copy-paste errors — and every document automatically calculates CGST/SGST and generates a clean, downloadable PDF.

A live stock monitor tracks inventory levels and valuation as sales happen. A dedicated payment tracking module logs every transaction across cash, UPI, and bank transfer, giving an always-current picture of what's paid and what's outstanding.

Instead of routing every invoice through a generic no-reply system, HMC Billing sends emails directly from the user's own personal mail account — so when a customer receives an invoice, it lands in their inbox from someone real, not a faceless system. Each email uses a professionally designed template with the invoice details laid out cleanly, keeping every communication on-brand and personal, exactly how a trading company builds trust with its customers.

Every invoice also gets a public, shareable URL — no login required. Customers can open it in a browser to view the invoice or download it as a PDF directly, without waiting on an email attachment or needing an account. It's a small detail that removes friction at exactly the point where a customer wants to check or forward their invoice.

Every document generated on the platform — quotations, proformas, invoices — is automatically backed up to Google Drive. No manual exports, no risk of losing records if something goes wrong locally. It's built-in peace of mind for a business that now runs entirely on digital records instead of paper and spreadsheets.

The standout feature: an AI-powered chat assistant that generates fully formatted, GST-compliant invoices from plain language. Type "Invoice for Ravi Kumar, 10 items at ₹800, 18% GST" and it builds the invoice — no forms, no manual entry. This cut invoice generation time by 70%.

Built with React.js and Next.js on the frontend, Node.js and Express on the backend, PostgreSQL for data integrity across invoices, customers, and stock, and REST APIs throughout — deployed on Vercel.

Hirani Marketing Combines now runs its billing operation on the platform every day. Excel is gone, GST math happens automatically, invoices go out from a real inbox with a shareable link attached, and every document is safely backed up — with the AI assistant turning what used to take minutes into seconds.