An AI receptionist books a plumber 5-7 extra jobs a week
In plain words
A builder set up an AI voice receptionist for a small plumbing crew whose owner was always under a sink. It answers 24/7, books into Google Calendar and logs every call to a sheet.
What happened: 5-7 extra jobs a week that would have gone to voicemail; many came from 6pm-8am calls (their own figures)
These numbers come from the builder and haven't been checked independently.
Source: reddit.com ↗
How to do it yourself
Our suggested steps. The company didn't publish theirs.
- 1
Check your phone log: how many calls did you miss last month, and when?
- 2
Write down your services, service area, rough prices and what counts as an emergency.
- 3
Set up the voice agent, connect Google Calendar and a Google Sheet, and paste the prompt below.
- 4
Call it 20 times yourself as different customers and fix anything odd.
- 5
Turn it on for after-hours and missed calls first; review the call log weekly.
The instructions to give the AI
Paste this into Retell AI (the free plan is fine), swap the [brackets] for your details, and test it on a few real examples.
This is one part of the setup. It won't connect to your phone, inbox or other apps on its own; the steps above cover that.
Agent instructions (prompt)
You answer the phone for [business], a plumbing company in [area]. Get the caller's name, address and what's wrong, and ask if water is leaking right now. If yes, text [owner phone] immediately. Otherwise offer the next 2 free slots from the calendar and book one. Log every call in the sheet. Friendly, short, never quote a price.
[Highlighted] = replace with your own details before you run it.
What you should get back: "Hi, you've reached Mike's Plumbing — I can get you booked. What's going on?" … then a booked slot on the calendar and a new row in the call log.
Written by Quickly and Good, inspired by this case.
More detail: tools, prices and what you'll need
The company used: Retell AI or Vapi voice agent
You could use: Voice agent (Retell AI or Vapi) + Google Calendar + Google Sheets
- Retell AI
Phone voice agents that answer and make calls, book appointments and transfer.
Pay as you go, $0.07-$0.31/min; $10 free credit · Official site ↗
Prices from each tool's own pricing page, checked Oct 2026.
What you'll need
- ☐A phone number the agent can answer (from the voice platform or Twilio)
- ☐A voice-agent platform (e.g. Retell AI, Vapi or Synthflow)
- ☐Connection to your calendar or job system so it can actually book
- ☐A knowledge base: services, prices, hours, service area, FAQs
- ☐The agent instructions (prompt) and a call script
- ☐20+ test calls, including angry, confused and off-topic callers
- ☐Transfer to a human for emergencies and anything it is unsure about
- ☐Call-recording/AI disclosure that meets local rules
Can I do this myself?
Possible if you are comfortable wiring tools together and testing for a week or two. If not, hire a builder: most owners do.
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