Guides · Five topics
36 guides, each answering one question a shop owner actually asks — with the math worked out, the sources listed and the date it was last updated. In-depth guides are the place to start.
What to charge per hour, how markup differs from margin, what a truck really costs, and how flat-rate and time-and-materials pricing compare — the business math behind every ticket.
1.01In-depth guide
How flat-rate and time-and-materials prices are built, one job priced both ways, where a flat price stops paying, and how to switch one task over.
(322 − 85) ÷ 112.68 = 2.1033 h
1.02In-depth guide
Build an hourly labor rate from wage, labor burden, billable hours, overhead, truck cost and profit, with a fully worked three-tech shop example.
$112.68 ÷ (1 − 0.10) = $125.20
1.03In-depth guide
Markup is on cost, margin is on price. Formulas, a conversion table, the classic mistakes and a water heater swap with labor, parts, tax and card fees.
$250 ÷ (1 − 0.35) = $384.62
1.04In-depth guide
Work out a service truck's cost per mile and per billable hour from ownership and operating costs, using AAA 2026 data, with the IRS rate as a check.
$16,719.14 ÷ 1,216.8 h = $13.74
1.05Guide
What billable efficiency means, what published figures measure, how a labor rate moves from 50% to 75% billable, and how to measure your own shop.
1,872 h × 65% = 1,216.8 h
1.06Guide
Build an electrician's hourly rate from BLS wages, payroll costs, workers' comp, overhead, truck and profit, with a worked three-tech example.
1.07Guide
A flat parts multiplier and a sliding markup scale compared: the margin each really leaves, the tier-boundary trap, and how sales tax changes the base.
$10.01 × 1.75 = $17.52
1.08Guide
Build a flat-rate price book from your own numbers: task list, standard hours, billable rate, parts markup, callback allowance, price tiers and upkeep.
(1.5 × $112.68 + $85) × 1.02 = $259.10
1.09Guide
When your labor-rate math says you are under, size the gap, check how much volume you can lose, stage the increase and handle quotes and maintenance plans.
1.10Guide
Build a service-call fee from drive time, truck cost and any included diagnostic time, decide whether to credit it, and know the FTC Cooling-Off Rule.
(0.8333 h + 0.5 h) × $125.20 = $166.93 → $170
1.11Guide
Build an HVAC shop's hourly rate from BLS wages and payroll costs, then price a two-visit maintenance agreement from visit time, supplies and that rate.
1.12Guide
A plumbing job costed line by line: materials, loaded labor, overhead, sub, permit and disposal, then gross profit, net margin and profit per hour.
$3,450.00 − $3,233.55 = $216.45
1.13Guide
Labor burden built line by line for a plumber paid $30.67 an hour: Social Security, Medicare, FUTA, state unemployment, workers' comp and benefits.
$30.67 × 2,080 h = $63,793.60
1.14Guide
Which costs belong in a service shop's overhead, which belong elsewhere in the rate, and how to turn a year of overhead into a cost per billable hour.
1.15Guide
When you are the owner and the tech, pay yourself a wage line and keep profit separate. Worked rates at four settings, with SE tax and BLS wages.
1.16Guide
Price a callback at loaded labor plus parts, turn your callback rate into a flat-rate allowance, and see what manufacturer warranties leave on you.
How to write an estimate a customer understands, what card fees really cost, and when you charge sales tax — the paperwork that turns work into cash.
2.01Guide
Price added or removed scope at your shop rate, update the payment schedule, and see what California, New York and Ohio say about changes.
2.02Guide
What field-service software charges to take cards, Visa's surcharge rules, cash discounts vs surcharges, and how card fees cut into a job's profit.
$2,400 × 2.99% = $71.76
2.03Guide
How to size a deposit, split a job into progress payments, and price net terms, late fees and card fees, with a $9,800 example and state rules as pointers.
2.04Guide
What all 50 states and DC say about sales tax on plumbing, HVAC and electrical labor, what changes the answer, and who pays the tax on materials.
$1,100.00 × 7% = $77.00
2.05Guide
A plumbing estimate checklist: scope, options, exclusions, expiry, deposit, payment terms, change orders, the FTC Cooling-Off Rule and license numbers.
Pipe volume, water heater sizing and what a water heater swap should cost — the numbers a plumber checks before buying parts, with the formulas and sources shown.
3.01Guide
Gallons per 100 feet for copper K, L and M, PEX, PVC Schedule 40 and CPVC, computed from published inside diameters, with wait-time and flushing math.
π ÷ 4 × ID² × 12 ÷ 231 = 0.0408 × ID²
3.02Guide
A contractor-side worked example: heater, parts, permit, haul-away and labor at your shop rate, a margin check, and why average cost pages miss your job.
$1,437.50 ÷ $1,085 − 1 = 32.49%
3.03Guide
Add up the fixtures that run together, turn gpm and temperature rise into Btu/h and kW, and see what gas and electric units can deliver.
3.04Guide
Size a tank by first-hour rating against peak-hour demand and a tankless unit by gpm and temperature rise, with the Btu/h and kW math worked out.
199,000 × 0.95 ÷ (500 × 77) = 4.91 gpm
3.05Guide
How to turn gpm and inside diameter into feet per second, what copper and PEX makers say about velocity limits, and what a faster pipe costs in psi.
Room cooling estimates, voltage drop and the 2026 refrigerant rules — quick math that always points back to the code and the equipment maker’s instructions.
4.01Guide
What ENERGY STAR's room AC chart says about BTU per square foot, how its four adjustments work, and why whole houses need a Manual J load.
9,000 × 0.90 + 2 × 600 = 9,300 BTU/h
4.02Guide
Often yes: since July 27, 2026, EPA lets you install R-410A AC and heat pump equipment made in or imported to the U.S. before 2025. Dates, NY, quoting.
4.03Guide
How the equal-friction method turns static pressure, length and airflow into a round duct size, with a worked example and the velocity check.
4.04Guide
How to turn kW or kVA into amps on single-phase and three-phase supplies, where power factor and line-to-line voltage come in, and the nameplate check.
4.05Guide
How to work voltage drop with the K-factor formula, copper vs aluminum, single vs three phase, and what the NEC's 3% and 5% notes really say.
√3 × 12.9 × 150 × 200 ÷ 211,600 = 3.17 V
Plain comparisons of the scheduling, dispatch, estimating and invoicing software small trade shops actually use — built from public pricing and documentation, dated, with the total cost spelled out.
5.01Guide
Yearly cost to send estimates and invoices from a one-truck shop with QuickBooks, Jobber, Joist and Invoice Simple, card fees included, October 2026.
5.02Guide
What Jobber, Housecall Pro, Service Fusion, Workiz, FieldEdge and ServiceTitan publish about auto-renewal, notice, exit fees and price increases.
5.03Guide
Eight field service apps for 1-5 tech plumbing shops: prices, seat rules, card rates and contract terms as published October 4, 2026, and who each fits.
$2,748.00 ÷ 3,650.4 h = $0.75
5.04Guide
Jobber and Housecall Pro prices as of October 4, 2026, with yearly cost for 1-, 3- and 8-person shops including card fees, worked out line by line.
225 × $11.10 = $2,497.50
5.05Guide
What ServiceTitan publishes, what its SEC filings say about contracts and onboarding, third-party price ranges labeled as such, and demo questions.
3 × $245 × 12 = $8,820