The answer depends on one number: how many calls are you missing, and what is each of those calls worth.
For a plumber missing 10 calls per week at $400 average job value and 35% conversion rate, those missed calls represent $7,280 per month in potential revenue. An AI receptionist costs $49-199 per month. The math is not close. Recovering even one call per week more than pays for it.
For a business that gets two inbound calls per week and answers both of them, the math is different. At very low call volumes, an AI receptionist is an expense without a return.
AI receptionists cost $49-199/month or $588-2,388/year. Contractors miss 27-74% of inbound calls. At $350-500 average job value and 35% conversion, recovering 2 calls per week generates $12,740-$18,200 additional annual revenue. One recovered call typically pays for a full month of service. Not worth it for very low call volume businesses or those with full existing coverage. Worth it for almost every active contractor missing calls on job sites.
Inbound calls per week: 35
Miss rate on job sites: 30% = 10.5 missed calls/week
Calls recovered by AI: 8 per week (some will still not convert)
Average job value: $350
Conversion rate on answered calls: 35%
Additional weekly revenue: 8 x 35% x $350 = $980/week
Additional annual revenue: $50,960
Annual cost of AI receptionist: $2,148 (Dolfyn at $179/mo)
Return on investment: 2,274%
That math is conservative. It uses a 35% conversion rate, assumes 2.5 calls per week still don't convert even when answered, and uses $350 as a job value — lower than most HVAC averages. The actual return for most contractors is higher.
Contractors who run their own operation are typically available during business hours, even if they're on jobs. The real gap is after hours — evenings, weekends, holidays. Research shows roughly 40% of service business bookings happen outside regular hours. For HVAC specifically, emergency calls after 5pm during heat waves and cold snaps are often the highest-value calls of the month.
A contractor who answers business-hours calls reasonably well but sends everything after 5pm to voicemail is missing roughly 40% of their inbound volume. At zero additional staffing cost, an AI closes that window entirely.
Cost and coverage are one thing. Whether the AI actually represents your business well is another. A generic AI that sounds robotic, gives wrong information, or fumbles emergency calls creates a different kind of cost — callers who had a bad first impression and don't come back.
This is where the done-for-you versus self-serve distinction matters. A self-configured AI running on a generic template performs differently from one built around your specific business, reviewed daily, and adjusted when something goes wrong. The $49 plan and the $179 plan are not the same product. The ROI calculation above assumes the AI handles calls well — which requires the setup to be right in the first place.
Two things worth doing before choosing a plan. First, count your missed calls for one week — check your phone's missed call log and note how many went to voicemail or were never returned. Multiply that by your average job value and your conversion rate. That number is the upper bound of what an AI could recover. Second, most AI receptionist tools offer free trials. Dolfyn offers two weeks with no credit card. Use the trial to verify the agent actually handles your calls correctly before committing.
Dolfyn's 2-week free trial lets you see exactly how many calls get captured and what they're worth before you pay anything.
Start Your Free TrialRelated: Receptionist Salary vs AI Cost · Contractor Missed Call Revenue Loss · How Much Does an AI Receptionist Cost