Suresh's Invoice Paid Board

I photograph the bills my clients raise, and one board tells me which ones the customer has actually paid.

Who this is for

Suresh Iyer runs a chartered accountant's practice above a medical shop in Saibaba Colony, Coimbatore. It is him, two article clerks, and about forty small clients: a hardware shop, a tuition centre, three transporters, a lady who supplies idli batter to hostels. The moment is the fourth of the month, when Ramesh from the hardware shop sends fourteen photographs of his invoice book and asks Suresh how much is still outstanding.

How the job is done today

The bills come as photographs into a WhatsApp group. Handwritten carbon copies, sometimes at an angle, sometimes with a thumb in the corner. A clerk types them into an Excel sheet named Ramesh_Sales_final2. Payments arrive separately, as UPI screenshots or as a line in the bank statement, and nobody writes down which bill the money was for. So on the fourth of the month Suresh calls Ramesh, Ramesh calls his own customers, and by evening somebody guesses that the Rs 18,400 that came on the 22nd was probably against two bills, or maybe three.

The screens, in order

1. Add a bill — Suresh or a clerk puts up the photograph of the handwritten bill and types the four things off it that anybody will ever need.
2. The board — Every bill for one client sits in two columns, not paid and paid, so the pending total is visible without adding anything up.
3. Money came in — When a payment lands, this screen shows the unpaid bills for that client and lets him tick off the ones the money covers.
4. One client's page — Everything for Ramesh in one place, so when he rings, Suresh reads the answer off the phone instead of promising to call back.
5. Still pending list — A plain list of what is unpaid and how old it is, ready to be sent to the client as a screenshot.

What it keeps track of

• Clients — the business name, the person Suresh actually talks to, their phone number
• Bills — which client, the photo of the bill, bill number, date on the bill, who it was billed to, the amount, paid or part paid or not paid
• Payments — which client, how much came, which day, how it came, and which bills it was put against

The one decision that matters

Should the site try to read the handwriting out of the photograph by itself, or should a person type four things while looking at it. Reading it automatically sounds like the whole point, but these are carbon copies in three different hands, with a nine that looks like a four and an amount written twice. A wrong figure that nobody checked is worse than no figure, because it goes into a return. So type it in. Four fields takes fifteen seconds, and the photograph stays next to the numbers forever, so when the customer argues about the amount, Suresh has the bill in Ramesh's own handwriting on the screen.

What to leave out of the first version

Leave out sending reminders to the client's customers. Suresh is not going to chase Ramesh's buyers, and the day the site starts messaging strangers is the day he has to explain himself to them. Also leave out tax working, ageing buckets and any report with more than one column. The first version only has to answer one question, which bills are still unpaid, and it should answer it faster than a phone call.

How you would know it worked

Ramesh rings on the fourth of the month, and Suresh answers the pending amount while still on the call, without opening Excel, without asking a clerk, and without saying he will check and call back.

Build it

Paste this in and let it run.

I am a chartered accountant in Coimbatore with about forty small clients, and their sales bills reach me as photographs of handwritten invoice books. Make me a website where I pick a client, put up the photo of a bill and type only the bill number, the date, who it was billed to and the amount, and it saves the photo alongside. Then show me that client's bills in two columns, unpaid and paid, with the pending total at the top. When money comes in I want to enter the amount and the date and tick which bills it covers, including part payment. Give me one page per client that I can open on my phone and read out when they call, and a simple pending list I can screenshot and send them. Two of my clerks should be able to add bills as well.