Portfolio Case Study · AI & Automation · Voice AI
A Multi-Tenant AI Voice-Calling CRM for Real Estate
An AI agent that phones leads, qualifies them, books consultations, and follows up — across three voice providers, with TCPA compliance built into the code.
Summary: AbedinTech engineered a multi-tenant AI voice-calling CRM for real estate. An AI agent phones leads, qualifies them against a per-tenant knowledge base, answers their questions, books consultations with calendar awareness, and follows up by SMS and email — with TCPA compliance enforced in code. Three interchangeable voice backends (Twilio, Telnyx, and Retell AI) share one CRM, scheduling, and compliance core.
Project at a Glance
| Project type | AI voice agent & CRM platform development |
| Architecture | Django 5 + DRF backend, FastAPI voice relay, React 18 (Vite, TypeScript) frontend |
| Voice & AI | Twilio, Telnyx, Retell AI; OpenAI tool-calling |
| Focus | Automated lead calling, compliance, provider flexibility |
| Quality | 68% test-coverage gate enforced in CI |
The Challenge
Automating outbound calls with AI is deceptively hard. Get any of these wrong and the system is unusable — or illegal:
Outbound calling is governed by TCPA rules. Compliance can’t be a policy document — it has to be enforced in the code path itself.
Twilio, Telnyx, and managed agents like Retell AI each work differently. Betting the whole product on one is a business risk.
A multi-tenant platform must keep every tenant’s leads, knowledge base, and settings cleanly isolated on shared infrastructure.
The Solution
An AI agent that actually converses
An OpenAI tool-calling loop drives the call — qualifying the lead, answering questions from the tenant’s knowledge base, and taking real actions like booking a consultation.
Three interchangeable voice paths
Twilio, self-hosted Telnyx, or managed Retell AI — all sharing one CRM, scheduling, and compliance core, so the voice provider becomes a swappable choice rather than a lock-in.
Calendar-aware booking
Native Google Calendar integration with busy-time awareness means the agent books consultations into slots that are actually free.
Automated SMS & email follow-up
After the call, the system follows up across channels to keep leads warm and move them toward a booking.
A TCPA compliance gate in code
Compliance rules are enforced programmatically before calls go out — a guarantee, not a guideline.
Architecture & Engineering
A Django 5 + DRF core owns the CRM, scheduling, and compliance logic, while a dedicated FastAPI voice relay handles the real-time call media; the frontend is React 18 with Vite and TypeScript. Speech-to-text and text-to-speech run at the carrier edge, with text frames exchanged with the backend. Every route is multi-tenant with tenant resolution built in, the database is Postgres, and quality is held by a 68% coverage gate in CI alongside documented, regression-blocking security guarantees.
Results & Impact
Technology Stack
Want an AI voice agent for your business?
AbedinTech builds compliant, multi-tenant AI calling and CRM systems. Get a proposal to scope yours.
Frequently Asked Questions
Can AI make and handle phone calls to leads?
Yes. An AI voice agent can place outbound calls, hold a natural conversation using an OpenAI tool-calling loop, qualify the lead, answer questions from a knowledge base, and take actions like booking a consultation — then follow up by SMS and email.
How is TCPA compliance handled in AI calling?
In this platform, TCPA compliance is enforced directly in the code path — a compliance gate checks rules before calls are placed, so compliance is guaranteed by the system rather than left to manual process.
Can an AI calling system integrate with my calendar?
Yes. This system integrates with Google Calendar and is aware of busy times, so the AI books consultations only into genuinely free slots.
Can AbedinTech build a custom AI voice-calling system?
Yes. AbedinTech builds multi-tenant AI voice-calling and CRM platforms with swappable voice providers, calendar booking, follow-up automation, and compliance enforced in code.