A one-person trade business needs to send invoices. Most platforms charge a monthly fee for features it will never touch. This one runs inside the tools it already has open.
A one-person contractor needs to send invoices. The usual options are writing them by hand, a word-processor template, or an invoicing platform with a monthly fee for team management, inventory tracking and CRM pipelines. The actual job is one thing: generate a professional invoice, track it, and send it.
The tools weren't built for people like him. They were built for companies that had outgrown the problem he was trying to solve for the first time.
He already had Google Workspace through his email. The solution had to live there: no new accounts, no new passwords, no new monthly charges. Google Sheets as the ledger, Google Docs as the invoice template, Apps Script as the glue.
This constraint eliminated entire categories of complexity. No server, no database, no deployment pipeline. The entire tool runs inside Google's infrastructure with zero hosting cost.
LUXIGA Bill is a complete invoicing system that runs inside Google Sheets. The web app handles everything: client management, line-item entry with live calculation, tax computation, and one-click invoice generation.
Line items calculate dynamically. Quantity × rate updates the subtotal in real time. Tax is computed on the subtotal. The total reflects everything as you type. When you click "Generate Invoice," Apps Script renders the invoice from an HTML template and saves it as a PDF.
The best tool for a one-person operation is the one that doesn't require a second person to manage.
The Sheet has dedicated tabs: Invoices (the ledger), Clients (contact details), and Settings (business info, tax rate, invoice numbering). The sidebar reads and writes to these tabs through Apps Script.
All line-item math happens client-side for instant feedback. When saved, the invoice writes one row to the Invoices tab and one row per line item to a separate sheet, so the ledger stays queryable with any number of line items.
The core invoicing flow is live: create, calculate, generate, save the PDF to a per-client folder, and send by email.