Auto Diagnostic Service Break-Even: About $27K Monthly Revenue

Break-Even Metric Cards

Fixed costs $20.9K/mo Base overhead load

Contribution margin 78% After variable spend

Break-even revenue $26.7K/mo Monthly target

Break-even timing Month 18 First profit month

Break-Even Calculator

Break-even calculator

Use this to test monthly revenue, variable expenses, and fixed costs against break-even for an auto diagnostic service.

Lean Base Full

Monthly revenue Revenue sets the margin left to cover fixed costs each month. $ Low sales High sales Variable expenses Use the costs that rise with more diagnostic work. $ Lean costs Heavy costs

Money available to cover fixed costs $30,362 $38,000 revenue - $7,638 variable expenses

Margin ratio

80%

Covers fixed costs

Yes

Fixed monthly costs This is the monthly cost base break-even must cover. $ Low overhead High overhead

Break-even chart Revenue Total costs

Which auto diagnostic service expenses stay fixed, and which move with sales?

Cost classification

Break-even is only useful if each expense behaves like the model says it does. In this shop, payroll step-ups and revenue-linked software fees matter more than small office overhead.

Expense	Cost	Break-Even Treatment	Common Mistake
Facility Rent ($4,000/month)	Fixed	Count the full monthly rent in fixed overhead from Month 1 through Month 60.	Modeling rent as a percent of revenue.
Utilities (Electricity, Water, Gas) ($800/month)	Semi-variable	Keep the base monthly bill in overhead and flex usage as bay hours rise.	Treating the full utility bill as fixed when shop hours expand.
Accounting & Legal Fees (General) ($700/month)	Semi-fixed	Hold the retainer flat until contracts, compliance, or entity work requires a higher monthly level.	Spreading general professional fees across each job.
Lead Diagnostic Technician / Manager ($85,000/year)	Semi-fixed	Include the salary as management capacity until another manager-level role is needed.	Treating salaried management time as per-job labor.
Diagnostic Technician ($60,000/year per FTE)	Semi-fixed	Add payroll in FTE steps as staffing grows from 1.0 in the first year to 3.0 by Year 5.	Ignoring break-even jumps when adding technician FTEs.
Customer Service / Admin Assistant ($40,000/year; 0.5 FTE first year)	Semi-fixed	Model admin payroll in staffing steps, not by each diagnostic ticket.	Leaving half-time admin out of fixed payroll.
Diagnostic Software Licenses & Data (5% of revenue in first year)	Variable	Apply the percentage directly against revenue, falling to 3% by Year 5.	Burying software subscriptions in overhead.
Marketing & Advertising (10% of revenue in first year)	Variable	Tie online ad spend to revenue for break-even, then reduce the rate to 7% by Year 5.	Using only the annual marketing budget and missing CAC pressure.

How do lean, base, and full operating setups change break-even for an auto diagnostic service?

Scenario table

Lean stays below break-even, base gets past it, and full adds cushion. Revenue rises faster than fixed payroll and overhead, so technician use and job mix drive the shift.

Planning assumptions only; these scenario figures are not guarantees.

Scenario	Monthly Revenue	Variable Costs	Fixed Costs	CM Ratio	Operating Profit	Break-Even Signal
Lean launch shop	$138k	$364k	$250k	78%	-$121k	Still below break-even.
Base staffed shop	$380k	$917k	$317k	79.9%	$47k	Past break-even around Month 18.
Full utilization shop	$686k	$1.48M	$408k	82%	$267k	Builds a wider cushion.

What pushes an auto diagnostic service below break-even?

Stress test

The plan only clears break-even if monthly revenue holds near $26,731 and the 78% contribution margin (share left after variable costs) stays intact. A small drop in bookings, a $1,000 fixed-cost bump, or a 1-point margin hit can erase the cushion fast.

Stress Case	Changed Assumption	Break-Even Revenue	Revenue Gap	Risk Signal
Current plan	No change.	$26,731	$0 gap	At the line; any miss turns into loss.
Revenue shortfall	Monthly bookings fall by 10 jobs.	$26,731	$1,802 gap	A small volume miss cuts contribution fast.
Fixed-cost pressure	Fixed monthly costs rise by $1,000.	$28,013	$1,282 gap	Higher overhead raises the revenue floor.
Margin pressure	Contribution margin falls by 1 point.	$27,078	$347 gap	Small fee or labor pressure lifts the break-even line.
Combined pressure	Bookings fall by 10 jobs, fixed costs rise $1,000, and margin falls 1 point.	$28,377	$1,646 gap	These pressures stack and shrink the cushion fast.

Is this auto diagnostic service ready to break even before you sign the bay lease and buy the scanners?

Founder checklist

Confirm the job flow, ticket mix, and cash burn first. The model only works if you can reach 116 jobs a month, hold a $231 weighted average ticket, and still fund the opening capex and payroll ramp.

1Demand Proof116 jobs/mo

Prove booked demand can reach at least 116 jobs a month before you lock the bay lease, since that is the volume behind the break-even case.

2Ticket Mix$231 WAT

Verify the blended ticket stays near $231 across all three services, because job volume alone will not cover the plan if pricing slips.

3Service Mix70/20/10

Hold Year 1 close to 70% comprehensive diagnostics, 20% pre-purchase inspections, and 10% B2B diagnostics, or the ticket and hour math will drift.

4Margin Load22% rev

Keep software, tool calibration, training, and online ad spend near 22% of revenue so contribution margin, the cash left after variable costs, stays around 78%.

5Payroll Burn$20.9K/mo

Check that $4,000 rent, $500 insurance, and Year 1 payroll of about $13,750 a month still fit the ramp, because the business starts near $20,850 in monthly burn before growth catches up.

6Capex RunwayMonth 18 / $583K

Verify scanner coverage, the $60,000 lift and workshop gear, and the rest of the $215,000 capex before you commit, and keep cash for the Month 18 break-even path and the $583,000 low point in Month 19.