Sample case study: the plumbing company and the Friday invoice scramble
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The business
A plumbing company with four technicians and one office manager. The technicians are out in trucks all day. The office manager, we'll call her Dana, handles scheduling, calls, and invoices.
The problem
Each technician wrote job notes on a carbon-copy pad: what they did, parts used, time on site. At the end of the week they handed the pads to Dana. On Friday afternoon she typed everything into an invoice template, one by one, squinting at handwriting.
In this example, that took most of Friday afternoon, and invoices went out days after the work. Slow invoices meant slow payment. A few jobs also went out with parts missing from the bill because the note was unreadable.
What got built
The helper skipped anything fancy and did three things.
- A form for the technicians' phones. Six fields: customer, address, work done, parts used, hours, and a photo if they had one. It takes about two minutes at the end of a job.
- A sheet that collects the answers. Each submission becomes a row, with a date and the technician's name.
- An invoice template that Dana fills from the row. She copies from a sheet instead of deciphering handwriting. A further step could fill the template on its own, but they held off, because Dana wanted to read each invoice anyway.
The phones already had a browser and a data plan. The form's link was saved to each tech's home screen.
What went wrong
For the first week, nobody used it. The techs kept writing on the pads and told Dana they'd enter the notes "when they got a minute." That minute never came.
The helper sat with two technicians at the end of a day and watched. The first form had ten fields, including some that didn't apply to most jobs. It also asked for a customer's full address typed out, which is annoying on a phone. Cutting it to six fields and switching the address to a quick lookup fixed most of it.
The other thing was the habit. They set a switch date and told everyone the pads were done after that Friday. The old pads came out of the trucks.
What changed
In this example:
- Invoices went out the same day or next morning, not the following week
- Dana's Friday afternoon was free
- Fewer parts were missing from bills, because techs typed them in while they remembered
Again, these are illustrative. In a real job you'd measure: how long between job and invoice before and after, and how many invoices needed corrections.
What this sample leaves out
It doesn't show cost, or the one tech who never warmed to the form and needed a second visit. It also skips the question of what happens when a phone has no signal at a job site. In a real project that would need an answer, perhaps a form that works offline or a rule to enter notes once back in range.
What to take from it
The fix only worked once the people using it had a say in it. That's the pattern in teaching staff a new tool: watch them use it, cut what gets in the way, and set a date.