Invoice Communication System  ·  Google Sheets · Gmail · Drive

Every invoice, on time.
Every client, looked after. Automatically.

A Sheets-native engine that turns your two Google Sheets into an automated communication system — welcome mails, on-time invoice sharing, gentle reminders and payment confirmations by Email + WhatsApp.

No new appNo migrationYour team already knows Sheets
See walkthrough What you get
Neutral white-label — add your own branding during setup. Engine stays linked to a private library.

What it is

You stay in Google Sheets, Gmail and Drive. The system handles the remembering, formatting and sending.

SheetWhat you do daily
Client MasterClient Data · Invoice Register · Payment Register · Communication Log (audit)
SettingsTemplates, reminder schedule and branding — set once, rarely opened
In one line: You do the 1-minute human part. The system does the remembering, formatting and sending — on both channels.

Problems it solves

ProblemWithout a systemWith this system
Welcome mail forgottenOnboarded, no welcome for 3 days.Queued when you add Client Name + Email + Services in Client Data. Once.
Invoices go out lateDrive link says ‘Request Access’.Paste in Invoice Link → auto Anyone with link → Viewer. Send Invoice.
Follow-ups are awkwardManual nudge 10 days late.Pre-Due -5/-2 & Overdue +2/+5/+10 then weekly, business-day gated. Stops at Rs. 0.
No record of what was sentSearch Gmail.Communication Log + View Invoice History.
Inconsistent toneThree people, three styles.Central templates with {{Placeholders}}.
Email + WhatsApp retypingRetype on WhatsApp.Equal channels, per-client toggles.

Time saved

WorkflowManualWith system
Add a new clientCreate row, invent ID, remember welcome~30 secondsClient Name + Billing TypeClient ID in 2s
Create & share an invoiceExport, fix sharing, compose, attach~1 minute — paste link → Send Invoice
Record paymentType, recalc, compose receipt~45 seconds — pre-filled balance, sends receipt
Daily follow-ups5–15 manual mails0 minutesPreview RemindersSend Due Reminders or 4×/day auto

~30 retainer clients → 12–15 hrs/month recovered. Not by working faster — by not re-typing the same four messages.

How it keeps you organized

Four tabs, one flow — no hidden database.

Sheets flow · Data moves left to right, every send is logged.

01 — Client Data
Client directory

One row per client or contact.

Client NameMonthly FeeDue Day
02 — Invoice Register
Invoice queue

You fill three fields: Client, Amount and Drive link — nothing else.

ClientAmountDrive Link
03 — Payment Register
Payments

Rarely typed. Dialog validates, updates Received and Balance Due.

ReceivedBalance Due
Communication Log — single source of truth
Every Email / WhatsApp logged · activity · channel · status · time · newest on top
View Invoice History

Rename-proof

Works even if you rename tabs.

Safe by design

Formulas and IDs self-maintain — no breakage.

How it stops forgetting

  1. On creation: Due Date auto-fills if blank.
  2. On schedule: Scans 4×/day on business days. Pre-due fires even without an invoice row.
  3. Before sending: Preview before you send — safe dry-run, sends nothing.

Stops automatically when paid.

A system, not just a tool

Auto + manual control

Daily auto scans + Send Due / Preview / Immediate / Test Email Delivery.

Templates = your voice

Welcome · Invoice · Pre-Due 1/2 · Overdue 1/2/3 · Recurring · Payment Confirmation with {{Placeholders}}.

Two-level control

Master switches + per-client/per-invoice Both / Email / WhatsApp in Automation Control.

Docs that help

1-page Quick Start + full SOP. New teammate productive in under an hour.

Walkthrough — one client, end to end

Client: Aravalli & Co. · Nisha Rao · nisha@aravalli.co · +91 98765 43210 · Brand + Performance · Rs. 42,000 · Advance · Due Day 5

StepWhat you doResult
1  Add client (30s)Client DataB Aravalli & Co. + H AdvanceCL00042Welcome eligible
2  Create invoice (1m)Upload PDF to Drive → Invoice Register: B/E/F → leave D Due Date blank05-Sep-2026 auto
3  ShareSelect row → Send InvoiceBranded mail + WhatsApp; Invoice · Success
4  RemindersNo actionPre-Due -5/-2 on 31 Aug & 3 Sep
5  Partial payRecord Payment Rs. 20,000 UPIBalance 22,000 · Partially Paid
6  NudgeSend Immediate ReminderSplit card AMOUNT PAID / BALANCE DUE
7  Final + receiptPay 22,000 → Send Payment ConfirmationFULLY PAID
8  AuditView Invoice History / Communication LogFull timeline INV00042

Email + WhatsApp — equal channels, same voice

Both channels send the same intent, in the native format for each. Automation Control + Notifications → Email/WhatsApp → Apply toggles per-client or globally. WhatsApp off? Email continues. Test via Test Email Delivery.

ChannelHow it sends
EmailBranded HTML (header, amount card, Drive button, signature) via Gmail aliases. Threaded.
WhatsAppMeta Cloud API v20.0 · UTILITY templates, versioned, {{1}} variables, optional document header.

What you get

Engine linked to private library — optional annual maintenance for future API updates; current version works indefinitely.

Quick reference — the 3 workflows

Add Client → Share Invoice → Record Payment. Full steps in the walkthrough above.

Common questions

Do we create PDF in Sheets? No — create outside (Docs/Canva), upload to Drive, paste link.

Without Drive link? Yes — confirm “Send WITHOUT attachment”.

Reminders need invoice row? Pre-due: no. Overdue/receipt: uses invoice row.

Stops after payment? Yes — stops automatically when paid.

WhatsApp off? Email alone works.

Edit tone? Yes — Subject/Content in Settings → Templates with {{Placeholders}}.

Works if you rename sheets? Yes.