AI Voice Agent Developer to Build and Deploy Production Voice AI System (VAPI / Retell AI)

We run a multi-location dental practice group and our front desk is drowning. We're handling 60 to 100 inbound calls per day across our locations and our staff is spending most of their time on routine appointment booking, rescheduling, and answering the same insurance questions over and over. We want to deploy an AI voice agent that takes over the routine call volume and frees our team to focus on patients in the chair. We also want to launch an outbound recall campaign to bring back patients who are overdue for cleanings. We need someone to build and ship both systems end to end. Not a demo, not a prototype — a production system that handles real call volume. What we need built: Inbound voice agent that handles new patient bookings, existing patient rescheduling and cancellations, basic FAQ (hours, location, insurance accepted), and warm transfers to a human when the situation calls for it. Must check real-time availability before confirming any appointment. Outbound voice agent that calls patients overdue for recall, delivers a friendly reminder, and books them directly into open slots if they're interested. Full CRM integration (we use HubSpot) — contacts updated, deal stages moved, follow-up sequences triggered automatically based on call outcome. Post-call summaries, transcripts, and recordings routed to the right place automatically. Calendar integration with our practice management system (we'll share details with shortlisted candidates). We're platform-agnostic. We've evaluated VAPI and Retell AI. If you have a strong opinion based on our use case, we want to hear it. This is a real build with a real budget. We are not looking for someone who will set up a flashy demo and disappear when things break in production. We need someone who has shipped voice agents that handle real inbound and outbound call volume in production. Please answer the following in your application: Have you shipped an autonomous voice agent to production? What platform did you use, what did it handle, and what were the actual results (call volume, booking rate, containment rate)? How would you approach the CRM integration — specifically, how does a call outcome translate into a pipeline action in HubSpot? VAPI or Retell for our use case — which would you choose and why?