General auto repair shop unit economics and KPIs
Illustrative case · Three-bay independent mechanical repair shop with two technicians and an owner service adviser · United States · illustrative case, no city selected
Explore this business · Unit economics and KPIs
The case earns $157.25 of contribution per billed technician-hour before the fixed roster and premises costs. Cash break-even is 192.4 billed technician-hours per month under the stated financing. Compare that requirement with usable capacity and actual demand before treating the format as viable.
Define the unit before comparing margins
The unit is one billed technician-hour plus its assumed associated parts sale. Variable cost includes the parts cost, shop consumables and processing fees. It does not mean a vehicle stays in the bay for exactly one hour or that an employee can bill every paid hour.
Contribution and break-even bridge
| Measure | Value |
|---|---|
| Average revenue per billed technician-hour | $225.00 |
| Variable cost per billed technician-hour | $67.75 |
| Contribution per billed technician-hour | $157.25 |
| Mature fixed operating costs / month | $28,207 |
| Scheduled principal + interest / month | $2,048 |
| Operating break-even billed technician-hours per month | 179.4 |
| Cash break-even billed technician-hours per month | 192.4 |
| Physical/roster capacity billed technician-hours per month | 284.3 |
| Mature modeled billed technician-hours per month | 235.0 |
Operating break-even equals monthly fixed costs divided by contribution per unit. Cash break-even adds scheduled principal and interest to that numerator. This is a steady-month test; it excludes changes in working capital and does not recover the opening investment.
What limits the number of units you can sell
The binding limit is the smaller of productive technician-hours and available bay-hours. In this case the skilled roster is the tighter constraint. A third bay improves scheduling flexibility but does not create another technician. Parts-delayed work and diagnostic uncertainty can further reduce usable capacity.
Track attendance, productive work and sold hours separately. Improving scheduling and parts readiness may create output within the existing roster, but selling excessive hours can increase returns and reputation damage. Capacity should describe work that can be completed to the promised standard.
| Input | Case assumption |
|---|---|
| Service bays | 3 |
| Available paid technician-hours / week | 80.0 |
| Maximum billed share of paid time | 82.0% |
| Mature billed technician-hours / month | 235.0 |
| Customer labor charge / billed hour | $135 |
| Parts revenue / billed hour | $90.00 |
| Cost of parts / billed hour | $55.00 |
| Shop consumables / billed hour | $6.00 |
| Available hours / bay / week | 40.0 |
| Payment processing / sales | 3.0% |
The operating dashboard to keep
| Metric | How to measure it | Why it matters |
|---|---|---|
| Billed hours per technician | Authorized labor invoiced against the paid roster. | Locate the actual capacity constraint. |
| Realized labor rate | Labor revenue divided by billed hours. | Detect discounts and unpaid work hidden by the posted rate. |
| Parts gross contribution | Parts sales less parts cost, returns and unrecovered special orders. | Test whether the assumed repair mix holds. |
| Bay cycle time | Arrival to completion, with waiting reasons. | Separate technician work from vehicles occupying space. |
| Comeback labor | Unpaid repeat work attributed to the original job. | Measure quality failures that consume paid capacity. |
Review these measures with the same service scope and period each time. Investigate changes in price, mix, timing and quality before assuming that a higher revenue total represents an improvement.
Billed hours differ from paid hours
Track diagnostic time, authorization waits, parts delays and rework. Increasing hourly sales requires either better usable time or a different mix; neither follows automatically from extra bays.
Contribution and break-even use the stated unit definition. Collect both its numerator and denominator over the same period. Compare the monthly demand scenarios before interpreting a mature-month threshold as an opening-year result.
Sources and scope
- Operating-case methodology · Checked 2026-10-01 · Authored illustrative assumptions and a 60-month model. Budget allowances, prices charged, demand, payroll, rent and financing are not observed local averages.
- EPA — Managing used oil: business questions · Checked 2026-10-01 · Used-oil generators include repair shops; management, storage and recycling responsibilities. Local requirements and other wastes need separate verification.