Part 01 · Build vs. buy · Residential
The algorithm no one is running
Every residential installer can tell you what their survey team costs. Almost none of them can tell you what a completed survey costs. Those are different numbers, and the gap between them is where the margin goes.
Ask an installer what a site survey costs and you usually get the same shape of answer. My surveyor makes about sixty-two. He does three, maybe four a day. Call it a hundred a survey. Cheaper than paying somebody else.
It is a reasonable answer. It is also wrong by roughly a factor of three, and it is wrong in two specific, predictable ways: the numerator is missing eight cost lines, and the denominator assumes a day that does not fit into a day.
Start with the denominator, because nobody checks it
A residential site survey takes an hour to an hour and a half on site. That is the figure installers give themselves, for a visit that measures the roof, gets into the attic, reads the main panel and assesses shading. Call it ninety minutes.
Then add the parts of the day that are not the survey. The drive between two jobs in the same metro. The morning at the shop loading gear. Lunch. The photo upload that has to happen somewhere with signal. The drive home, which is paid and is not billable to anybody.
| The day, honestly | Minutes |
|---|---|
| Paid workday | 480 |
| Shop, load-out, dispatch | −25 |
| Lunch | −30 |
| Photo upload and admin | −35 |
| Drive home | −45 |
| Left for surveying | 345 |
| Cost of one attempt (90 on site + 38 driving) | 128 |
| Attempts that fit in a day | 2.7 |
Not four. Not three. And an attempt is not a survey. Some percentage of those stops finds nobody home, finds a locked attic, or comes back failing QC because a panel label was never legible in any of the six photos taken of it. Every one of those consumes a full slot and produces nothing shippable.
Almost none of our rework traces to a photo taken wrong. It traces to a photo nobody took.
Now the numerator, which is missing eight lines
The wage is the line everybody has. Here are the ones that usually are not in the number:
| Line | Why it belongs in the survey cost |
|---|---|
| Payroll burden | Taxes, workers comp, benefits. On field labor this is rarely under a quarter of base pay. |
| Vehicle | Payment or depreciation, fuel, insurance, maintenance, tires. The truck exists to do surveys. |
| Devices and software | Phone, tablet, the measuring hardware, the app seats, the storage the photos land in. |
| Insurance and licensing | General liability, any state or municipal licensing the visit requires. |
| Recruiting and training | A surveyor who leaves at month nine took the ramp with them. Amortize it. |
| Dispatch and scheduling | Somebody books the homeowner, confirms, reschedules the no-show. That is labor. |
| No-shows and aborts | Paid slots that produce nothing. They do not disappear, they redistribute onto the surveys that did complete. |
| Rework | The resurvey is a second full cost against the same single deliverable. |
None of these are exotic. Each one is boring on its own. Stacked, they are most of the answer, because they attach to the day while the wage attaches to the hour, and the day holds fewer surveys than anyone budgeted for.
Run it on your own numbers
Below is the arithmetic, in the open. The defaults are a plausible mid-size residential installer. They are not your company. Change every one of them and see where you land.
Interactive model
Fully loaded cost per completed survey
Everything recomputes as you type. Nothing leaves your browser.
The person
The day
The lines nobody counts
What the number is for
Not for deciding that in-house surveying is a mistake. It is not. The number is for making the comparison an honest one, because the alternative gets quoted as a single all-in price per survey and the in-house option almost never does. One side of that comparison carries burden, windshield time, no-shows and rework. The other side is a line on an invoice. Until both sides are stated the same way, the cheaper option always looks like the one whose costs are hidden inside payroll.
Run it and one of three things happens. The gap is smaller than you expected, and you have a defensible reason to keep the crew. The gap is enormous, and you have a number to take to a partner. Or you cannot fill in half the inputs, which is its own finding.
What this model does not say
It says nothing about quality, turnaround, or coverage, and those decide more deals than cost per survey does. It also assumes a surveyor who is busy all day. If the calendar has holes in it, the real number is worse than what this returns, and Part 02 is about exactly that.
Put a real number against your own crew
We survey residential, commercial and utility-scale sites nationwide, and we will run this comparison against your actual volume before anybody talks about a contract.
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