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New Jersey Auto Repair Rules (N.J.A.C. 13:45A-26C) for Mobile Mechanics: Authorization, 5 Estimate Options, and Guarantees

Updated 2026-10-17. Sources are listed at the end.

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This is general information, not legal or tax advice. Rules vary by state and change often. Confirm with the official source linked in each section, or with a licensed attorney, CPA or insurance agent, before you act.

New Jersey’s rules for auto repair are in the Division of Consumer Affairs’ regulations under the Consumer Fraud Act. N.J.A.C. 13:45A-26C.2 lists acts that are deceptive practices for an “automotive repair dealer,” including when they’re done by any mechanic or employee of the business (N.J.A.C. 13:45A-26C.2). The Division also publishes a consumer Guide to Auto Repair.

Step 1: signed authorization, with the odometer reading

Before starting paid work, you need specific written authorization signed by the customer that states the repair requested or problem and the vehicle’s odometer reading. Oral authorization, logged with the date, time, name and phone number, is allowed only for after-hours drop-offs or when someone other than the customer brings the car (26C.2(a)2). On a driveway job you’re usually face to face, so get the signature.

Step 2: give an estimate, five ways allowed

Before work, you need one of these (26C.2(a)3.i):

  1. A written not-to-exceed price
  2. A written itemized breakdown of parts and labor. You may charge for diagnosis to produce it, but only if the customer agrees to the diagnostic charge in advance, and you can’t bill that diagnostic work twice if they then have you do the repair
  3. A written price for a specific named repair (the rule’s example is “valve job”)
  4. Written authorization to proceed up to a specific dollar amount, which then counts as the estimate
  5. A signed written waiver of the written estimate, plus oral approval of an estimated price, noted on the repair order with date, time, name and phone

Option 3 suits mobile techs who quote flat prices. Option 2 requires agreeing the diagnostic charge up front. See setting a diagnostic fee.

You can’t charge more than any estimated price without the customer’s oral or written consent, obtained after you find the estimate is too low and before doing the extra work. For oral consent, note on both the repair order and the invoice: date, time, who authorized, the phone number called, the additional parts and labor, and the total additional cost (26C.2(a)6).

New Jersey has no 10% allowance, unlike Washington, Illinois or Ohio. Every overage needs consent. Compare in the estimate & invoice guide.

Invoices, parts and guarantees

The sign

Dealers must post the regulation’s “A CUSTOMER OF THIS ESTABLISHMENT IS ENTITLED TO…” sign, which covers the estimate options, the waiver, signed authorization, the detailed invoice, returned parts and a written guarantee (26C.2(a)11). Mobile techs have no premises to post it in. Printing the same wording on your estimate form is a sensible practice, but it isn’t a legal substitute. Ask the Division of Consumer Affairs how it applies to you.

New Jersey paperwork checklist

  1. An authorization line with a signature and odometer reading.
  2. Pick an estimate method, usually a specific-repair price or an itemized breakdown with a pre-agreed diagnostic fee.
  3. A consent log for overages on both the repair order and the invoice.
  4. An itemized invoice with new/used/rebuilt marked on each part.
  5. A written guarantee that meets the disclosure list.

Build accurate estimates so you rarely need to ask for more: job quote & profit calculator.

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Sources