Voice AI

How I Built a Voice AI System That Qualifies Leads While You Sleep

A complete technical breakdown of the outbound voice AI + email automation system I built for an MCA lender. 100-120 calls/hour, 3x qualified lead volume, $0.12 per call.

CM
Chris Mott
Founder, ResultantAI
Jan 5, 2026 12 min read
Voice AI system dashboard
⚡ TL;DR
  • Built an outbound voice AI + email automation system for an MCA lender
  • Handles 100-120 calls/hour with consistent qualification questions
  • Reduced document collection time from 5 days to 1.5 days
  • 3x increase in qualified lead volume without additional headcount
3x
Qualified Lead Volume
$0.12
Cost Per Call
120
Calls Per Hour
75%
Time Saved

The Problem: Manual Lead Qualification Doesn't Scale

Jay runs an MCA (Merchant Cash Advance) lending operation. His team was spending 6+ hours daily calling leads, asking the same qualification questions:

At $25/hour for a caller doing 15-20 calls/hour, each qualified lead was costing $8-12 in labor alone. And the bigger problem was inconsistency — different reps captured data differently, creating chaos in the CRM.

The Solution: Voice AI + Automation Stack

System Architecture
📞
Retell AI
Make.com
📊
HubSpot
📧
Smartlead

Component 1: Retell AI for Voice

Retell handles phone conversations. The key is writing prompts that sound natural while extracting exact data points:

prompt.txt
# MCA Lead Qualification Agent

ROLE: You are Sarah, a funding specialist.
OBJECTIVE: Qualify business owners for MCAs.

QUALIFICATION CRITERIA:
1. Business age: Minimum 6 months
2. Monthly revenue: Minimum $10,000
3. Funding need: $5,000 - $500,000

CONVERSATION FLOW:
 Warm greeting (use their name)
 Confirm they're the business owner
 Ask about business age naturally
 Transition to revenue question
 Determine funding needs
 If qualified: schedule callback
💡 Pro Tip

The biggest mistake with voice AI prompts is being too robotic. Instead of "What is your monthly revenue?" use "And just to get a sense of your business size, roughly what do you guys do in monthly revenue?"

Component 2: Make.com for Data Orchestration

Make.com routes data between systems. When Retell completes a call, it triggers a webhook that:

Component 3: HubSpot for CRM & Lead Scoring

HubSpot serves as the single source of truth. The lead scoring model:

The Results: Before vs. After

"Chris built exactly what we needed — a system that qualifies leads while we sleep. The AI sounds natural, the workflows never break, and we've already 3x'd our qualified lead volume without hiring more reps."
Jay Jami, Jami Consulting

Key Lessons Learned

1. Prompt Engineering is Everything

I spent 40% of project time on prompts. The difference between good and great is 20% vs 45% qualification rate.

2. Build for Failure

The AI will make mistakes. If it can't extract data, flag for human review rather than guessing.

3. Start with High-Volume, Low-Stakes

Lead qualification is perfect — calls are short (2-4 min), questions predictable, and mistakes don't cost deals.

Frequently Asked Questions

How much does voice AI lead qualification cost? +

Voice AI typically costs $0.12-0.15 per call using Retell AI, compared to $3-5 for human reps. For 500+ calls/day, this means 90%+ cost savings.

What platforms are best for voice AI systems? +

For B2B lead qualification, Retell AI + Make.com + HubSpot is a proven stack. Retell handles voice, Make.com manages data flow, HubSpot serves as CRM.

Can voice AI handle complex questions? +

Yes, modern voice AI handles multi-branch conversations with conditional logic — verifying business age, revenue, funding needs with natural follow-up questions.

Want a System Like This?

I build voice AI systems for B2B service businesses. Let's talk about what 24/7 lead qualification could do for your pipeline.

Book a Strategy Call →
CM
Chris Mott
Founder, ResultantAI

Chris builds revenue systems for B2B service businesses — voice AI, workflow automation, and CRM architecture. He's shipped systems that generated $382K in pipeline for clients in the first 12 months.