Last month, I launched OnCrew — an AI-powered phone answering service built specifically for home service contractors (HVAC, plumbing, electrical, roofing).
Here is the problem I set out to solve and how I built it.
The Problem
A plumber in Van Nuys finishes a 12-hour day at 8 PM. He silences his phone. At 2 AM, a homeowner pipe bursts. They call. Voicemail. They call the next plumber on Google. That first plumber just lost a $4,200 emergency job in his sleep.
This happens thousands of times every night across LA alone. Contractors miss 40-60% of after-hours calls, and each missed call is worth $800-4,200 in lost revenue.
Traditional answering services charge $1-2 per minute and employ people reading scripts who cannot tell a burst pipe from a dripping faucet.
The Solution: OnCrew
OnCrew is an AI phone agent that:
- Answers every call 24/7 — no hold music, no voicemail
- Understands trade-specific language — knows the difference between a burst pipe and a quote request
- Triages by urgency — real emergencies get dispatched immediately, quotes get scheduled
- Dispatches the nearest tech in 90 seconds
- Costs $49/month flat — no per-minute billing
Tech Stack
- Frontend: Next.js 16 on Vercel
- Voice AI: Retell AI with custom Claude-powered LLM
- Telephony: Twilio for phone numbers and call routing
- Payments: Stripe with 14-day free trial
- Database: Supabase
- Notifications: Telegram bot for real-time alerts
How the AI Works
When a call comes in:
- Retell AI picks up and greets the caller naturally
- The AI asks targeted questions based on the trade (HVAC, plumbing, electrical)
- It classifies the call: emergency, urgent, or routine
- For emergencies: immediately notifies the contractor and dispatches
- For routine calls: books an appointment or takes a message
The AI (we named her Sarah) uses Claude as the underlying LLM with contractor-specific knowledge. She knows that no hot water in January is more urgent than in July. She knows a panel buzzing smell means dispatch now.
Results So Far
We just launched, so I am being honest — zero paying customers yet. But the tech works. You can call (818) 578-4783 right now and talk to Sarah yourself.
What I can tell you:
- Call pickup time: less than 1 second
- Available: 24/7/365
- Cost: $49/mo flat (vs $200-500/mo for human answering services)
What I Learned Building This
- Contractors do not care about AI — they care about not missing calls.
- Voice AI has gotten scary good — Retell + Claude produces conversations hard to distinguish from human.
- The trades are massively underserved by tech — most software is designed for office managers, not the guy in the truck at 8 PM.
- SEO for a new domain is brutal — fighting established players with similar names.
Try It
Check out OnCrew. 14-day free trial, no credit card required.
Or call (818) 578-4783 and see for yourself. Sarah picks up on the first ring.
Building in public. Follow along: @OnCrewAI
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