Can I charge for R&D and diagnostic time on a one-off build with no established procedure?
Short answer
Yes, and you should bill it as its own line item, separate from install labor. Figuring out how to fab a mount that doesn't exist yet or chasing a custom tune issue with no baseline is real shop time, not something you eat because there's no flat-rate number for it.
One-off work has no flat rate, so stop pricing it like it does
Flat rate manuals exist because someone already figured out how long a job takes on a known platform. A one-off build, a rare swap, or a tune on a combination nobody's dyno'd before has no manual entry, which means every hour your best guy spends test-fitting a bracket or chasing a fuel trim issue on a custom setup is real cost with no shortcut.
Bill it hourly at your shop rate, tracked honestly, and tell the customer up front that's how novel work gets priced. Customers chasing a build nobody else does understand this once you explain it plainly; they're often the ones most annoyed when a shop pretends to know an exact number for something that's never been done before.
Separate R&D time from install time on the invoice
Two line items: diagnostic or R&D hours at your rate, and install/assembly hours once the plan is set. This does two things. It shows the customer exactly what they're paying for instead of one mystery number, and it gives you a record of how much time novel work actually takes, which makes your next quote for something similar sharper.
Cap the R&D hours with a not-to-exceed number before you start, and call the customer if you're going to blow past it. An open-ended hourly clock on work the customer can't see or verify is the fastest way to lose their trust even when your hours are completely honest.
This is also where dyno time and tune iteration belong
Tuning a stock combination that's been done a thousand times takes an hour. Tuning a custom fuel system, oddball turbo, or engine combination that's never been on your dyno before can take four or five hours of pulls, log review, and adjustment. That's R&D time too, price it the same way, hourly with a stated cap, not folded into a flat 'tuning' charge that doesn't reflect the actual work.
Explaining R&D billing to a customer used to flat-rate pricing
Customer questions why the quote has an hourly R&D line instead of one flat number.
Customer
“Why is part of this hourly? Every other shop just gives me one number.”
You
“Because nobody's built this exact combination before, there's no manual to price it off. The install once we know the plan is a flat number. Figuring out the plan, the fab work, the tune iteration, that's billed hourly with a cap so you know the ceiling.”
Customer
“What if it goes over the cap?”
You
“I call you before it does, tell you where we're at and why, and you decide whether to keep going. You'll never get a surprise number at pickup.”
Do not say
- “It'll probably be around... (never quote a soft number on true R&D work, it becomes the number they hold you to)”
R&D time example on a custom turbo install
| R&D: bracket fab, fitment trial and error | 6 hrs @ $110/hr = $660 |
|---|---|
| R&D: tune iteration on a new combination | 4 hrs @ $110/hr = $440 |
| Install once plan is finalized | 10 hrs @ $110/hr = $1,100 |
| Total laborR&D is 50% of the labor total on a true one-off | $2,200 |
The math: R&D and diagnostic hours are billed at your standard shop rate, tracked and invoiced separately from install labor, with a stated not-to-exceed cap agreed before work starts.
Where owners get this wrong
- Folding unpaid R&D time into a flat quote and eating the overage yourself.
- Never telling the customer there's an hourly component until the invoice arrives.
- Letting R&D hours run with no cap and no check-in call.
Ask your version of this question
This is one business owner-tested take. Your shop size, trade, and team change the answer. Ask the exact version inside Ask a Shop Owner and get a response grounded in how owners like you actually handled it.
Now run it against your numbers.
This answer is written for shops in general. Inside Ask a Shop Owner it becomes your answer: your revenue, your crew, your market, your history. Ask "Can I charge for R&D and diagnostic time on a one-off build with no established procedure" and get the version that accounts for what you already told us.
Was this helpful?
One click. It tells us which answers to deepen and which questions we still owe you.
Not ready for a trial? Take the scripts with you.
Leave your email and we send three short notes over the next week showing how owners used answers like this one on a real decision. No newsletter, no drip forever.
Three emails, then it stops. Unsubscribe in one click. We never sell your email address.
Answered for these owners