Cost & Quoting

What Drives Cost Per Body When You Quote Trailers and Truck Bodies

How to build a quote that holds on a trailer or truck body: the real cost drivers per unit, how to load overhead, and the estimating errors that eat margin.

A trailer or truck body quote is a fabrication cost stack, and material yield sets the floor before labor is even counted. On a steel flatbed, raw material commonly runs 45 to 60 percent of cost per body, so a few points of scrap on plate and floor plank move the number more than any labor tweak. Build the material line from cut lists priced at current mill cost, then divide by yield: if a body needs 27 sq ft of usable skin but your nest yields only 84 percent, you buy roughly 32 sq ft and pay for the 5 sq ft drop on every unit. The Cost Per Body calculator rolls these lines into the per-unit figure you defend.

Weld labor is the second largest lever and the one most often guessed. Rather than reprice weld footage here, convert it to money: welder hours times a fully loaded shop rate. A frame carrying 143 ft of weld at 12 in per minute arc, scaled by a 2.5 setup-and-positioning multiplier, is around 6 labor hours. At a loaded rate of 65 to 95 dollars per hour, that single station is 390 to 570 dollars per body. Loaded means wage plus burden, benefits, and payroll tax, typically 1.35 to 1.55 times the base wage. Quote off base wage and you underrecover by a third on your single biggest labor cell.

Machine and station time carries overhead you must absorb, not just direct labor. The Paint Booth Capacity picture matters to cost because paint is usually the plant bottleneck: if a booth's good output is 1,676 bodies against 1,920 gross, every painted body must carry booth fixed cost across the achievable number, not the theoretical one. Divide annual booth burden, exhaust, filters, energy, and depreciation, by realistic good output. Quoting fixed cost against nameplate capacity spreads it too thin and leaves a gap you only find at year end when the booth ran 87 percent of gross.

Options and upfit content swing per-unit cost hard with volume, and this is where sales-driven quotes drift. The Option Package Cost calculator prices a bundle as vehicles times per-vehicle content times a capture factor plus fixed engineering and tooling. A liftgate-plus-lighting package with 1,800 dollars of install content and 4,000 dollars of one-time fixturing costs 1,800 plus 4,000 divided by run size. Over 100 units that is 1,840 per vehicle; over 10 units it is 2,200. Wiring Harness Labor works the same way: fixed setup of 250 dollars adds 2.50 per unit over 100 harnesses but 25.00 over ten. Never carry one run's per-unit option cost into a smaller order.

Scrap and rework must be priced as expected cost, not hoped away. The Rework Allowance calculator lets you carry a defensible percentage rather than a wish. If historical first-pass yield on finished bodies is 94 percent and the average rework touch costs 220 dollars in labor and material, expected rework per body is 0.06 times 220, about 13 dollars, plus scrap value on the panels that cannot be recovered. On a 12,000 dollar body that is roughly one point of margin. Estimators who zero out rework win the bid and lose the job; a 3 to 6 percent allowance on labor-intensive builds is realistic.

Compliance is a real cost center on regulated builds and is routinely omitted. Compliance Inspection Time captures DOT lighting checkout, brake and axle verification, VIN and placarding, and documentation. Budget it as inspector hours times loaded rate plus any third-party certification fee. A specialty tanker or a build crossing FMVSS requirements can absorb 2 to 6 inspection hours per unit; at 70 dollars loaded that is 140 to 420 dollars per body before any corrective action. Leave it out of the stack and your quote is short by a line the customer will still make you perform.

Overhead and margin turn cost into a sell price, and the order matters. Total your direct costs, material after yield, weld and assembly labor loaded, options, harness, rework allowance, and compliance, then apply a plant overhead burden, commonly 15 to 30 percent of direct cost for a fab shop, before margin. Apply margin last on the fully burdened cost. A defensible quote shows each line: a 12,000 dollar cost per body at 22 percent overhead becomes 14,640, and a 15 percent margin lands near 17,225. Margin on unburdened cost is the most common way shops quote low and bleed.

Estimates go wrong in predictable places, so audit for them. The three biggest leaks are quoting material at plan yield instead of demonstrated yield, using unloaded labor rates, and spreading fixed option or booth cost across nameplate rather than achievable volume. A fourth is model-mix blindness: averaging a heavy-content specialty unit with plain flatbeds hides that the specialty build loses money. Quote each configuration on its own cost stack, carry a rework allowance, and reconcile actuals back to the estimate after every run. One or two points of material yield and a correctly loaded weld rate typically decide whether a trailer program clears margin or eats it.

Published 2026-07-01.