How does flat-rate pricing work?
A flat-rate shop builds a pricebook with a fixed price for each common job. The price includes labor, parts, markup and usually a warranty. The tech finds the job in the book, quotes one price, and the customer approves before work starts. If the job takes longer, the price does not change.
Vendors and large service companies that use flat rate point to known costs for the customer and less reason to stretch the job. The drawback is that a job not in the book needs a quote, and a job that runs long eats margin.
How does time and materials work?
Time and materials bills labor at an hourly rate plus parts, often with a markup on parts. It is flexible when scope changes or a problem is bigger than expected. The cost is unpredictability. Customers can face a high bill after a long job, and hourly charges can look suspicious to a homeowner who cannot judge how long the work should take.
What does a worked example look like?
A water heater swap at 1418 Ridge Rd. Example numbers: parts cost $620, book time 3.5 hours, loaded labor cost $60 an hour.
Direct cost at book time: $620 + (3.5 x $60) = $830. A flat price at a 45 percent margin is $830 / 0.55 = $1,509.09, rounded to $1,509. If the job takes 5 hours, cost is $620 + (5 x $60) = $920, and the margin falls to (1,509 - 920) / 1,509 = 39.0 percent.
Under time and materials at $150 an hour with parts marked up 30 percent (620 x 1.30 = $806), the bill is (3.5 x 150) + 806 = $1,331 for a 3.5 hour job and (5 x 150) + 806 = $1,556 for a 5 hour job. Margin is 37.6 percent on the fast job and 40.9 percent on the slow one.
The customer pays $1,509 either way under flat rate. Under hourly they pay $1,331 or $1,556. The shop's margin is steadier under hourly, and the customer's price is steadier under flat rate.
Which jobs suit which method?
Flat rate fits repeatable work: water heater replacements, faucet and fixture installs, toilet repairs and drain clearing of a standard type. Time and materials fits unknown scope, such as tracing a leak behind a wall or a damaged main line. For work in between, quote a diagnostic fee first and a flat price once the cause is known.
How do you keep flat rate profitable?
Build the price from real costs. Total your monthly overhead and divide by billable hours to find the hourly rate you need, and remember that only part of a tech's day is billable. Update the pricebook when supplier prices move. Review actual hours against book time each month and fix the entries that run long.
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Sources: Roto-Rooter: Flat-Rate Pricing vs Hourly Pricing; ServiceTitan: Plumbing Pricing Guide