The situation is a daily one: the vehicle is in pieces and the work to be done is no longer the work that was accepted. What the rules require, what counts as proof of agreement, and the sequence that avoids a disputed invoice.
You must inform the customer as soon as additional work proves necessary — the DGCCRF says so expressly for work discovered once the vehicle has been dismantled — and you may invoice it only with their agreement: article 1193 of the Civil Code allows a contract to be modified only "by the mutual consent of the parties", and article L121-12 of the Consumer Code prohibits demanding payment for a service that was not the subject of a prior order. No particular form is imposed, but the burden of proof falls on you (article 1353 of the Civil Code): a dated written record — an email, an accepted follow-up quote, a recap by text message — is what makes the difference on the day it is disputed.
The starting point is not the mechanics, it is the contract. Once the customer has signed the repair order (ordre de réparation) or accepted the quote, you are both bound by what it says. The DGCCRF — the French consumer protection and competition authority — writes of the quote that it "firmly commits the professional, very precisely, as to the scope of the work, its cost and the agreed timescales", and that "once signed, it also serves as a repair order".
Article 1193 of the Civil Code draws the conclusion: "Contracts may be modified or revoked only by the mutual consent of the parties, or on the grounds that the law allows." A worn bush found during dismantling is not one of the grounds the law allows. To step outside the agreed scope, you need the other party's agreement.
The same DGCCRF fact sheet covers the case in black and white: "additional work may nevertheless prove necessary once the vehicle has been dismantled. The professional is then required to inform the consumer." The duty to inform therefore already exists. Agreement is the condition for being paid.
If you are rebuilding your workshop paperwork from scratch, start with the repair order and the details it is expected to carry.
Article L121-12 of the Consumer Code is drafted broadly: it prohibits "demanding immediate or deferred payment for goods or services supplied by a professional or, in the case of goods, demanding that they be returned or kept, where they have not been the subject of a prior order by the consumer". It covers services as much as goods: unordered labour falls within its scope.
Three practical consequences:
Only two exits exist in the texts, and neither concerns your ramp: article L121-14 sets aside the prior-agreement requirement for "payment resulting from a legislative or regulatory obligation", and article L121-13 allows a revision clause to be applied where its "terms were expressly defined and had the agreement of the parties at the time the contract was signed".
It is always the same sequence: the engine cover is on the floor, the technician calls the front desk, and there is half an hour left in the day. The mistake is almost never bad faith, it is momentum: you carry on "since you are in there", and you tell the customer when they collect the car.
The sequence that holds up:
None of this is imposed by any text: no rule requires a written follow-up quote. What is required is informing the customer; what is useful is the proof.
In a dispute the question is not "did the customer agree?" but "who has to show it?". Article 1353 of the Civil Code answers: "Whoever claims performance of an obligation must prove it." You are the one claiming payment, so proving the order is on you.
Two articles then frame the form:
Those two conditions are exactly what separates a good record from a poor one. A screenshot of a chat, editable and with no certain author, is worth less than an email sent from your software to the customer's recorded address, or a time-stamped acceptance on their tracking page.
In practice, always note: date and time, the name of the person you spoke to, the amount quoted, the timescale quoted, and the decision. Four lines on the file.
Refusal is their right, and it puts you at no fault. It raises three concrete questions.
Dismantling already done has a cost. It is only chargeable if it was announced beforehand: service prices must be known to the customer before they commit, and in its survey published on 4 June 2026 the DGCCRF noted precisely the recurring absence of displayed prices for services that are nonetheless invoiced to the consumer as a matter of course, such as diagnostic charges, storage charges and labour. If your diagnostic and dismantling charges are neither displayed nor written on the repair order, they will be hard to defend. Our guide on what a garage must display at reception covers this.
The timescale you announced remains yours. The DGCCRF recalls that where no time for the repair has been indicated, the professional then has 30 days to perform. A round trip to obtain agreement does not suspend that period: announce a new date at the same time as the follow-up quote.
The same fact sheet recalls that the garage "is required to return the vehicle entrusted to it in working order" and must hand back a car on which all safety-related work has been carried out. Where the refused work affects safety, write down what you flagged and what the customer refused, on the repair order and on the invoice. That record is what counts the day the question comes back.
Many workshop terms and conditions contain a sentence along the lines of: "the garage reserves the right to invoice any additional work made necessary by the condition of the vehicle". It does not amount to agreement.
The DGCCRF survey published on 4 June 2026 on the fairness of information given to consumers in vehicle servicing and repair lists, among the clauses found to be questionable or unlawful, those allowing a garage to invoice without regard to the quote or the repair order. The two other families singled out are flat-rate late-payment charges, which are reserved for business customers, and clauses limiting liability for theft of or damage to the vehicle. Of 1,600 establishments inspected in 2024, around 40 % led to enforcement action.
Article L121-13 of the Consumer Code shows where the limit lies: a revision clause escapes the prohibition only if its terms "were expressly defined" and had "the agreement of the parties at the time the contract was signed". A general formula that says neither what, nor how much, nor how does not meet that requirement. Time spent drafting a clause is better invested in a routine of phone call plus follow-up quote.
Two situations change the picture.
The insurance route. In body repair, the assessor's report determines what the insurer covers; the party you contracted with, the one who signed the repair order, is still the customer. When opening up a panel reveals further damage, both agreements are useful and neither replaces the other: the assessor's or insurer's for the funding, the customer's for the order. Get both in writing.
The business customer. Fleets, rental firms, companies: article L121-12 protects the "consumer", so it does not apply to them. Article 1193 of the Civil Code, on the other hand, applies to every contract without exception — an agreed deal can be modified only by the mutual consent of the parties. And on the ground it is often with business accounts that unapproved work ends in dispute, because the person dropping off the vehicle is not the person who signs the purchase order. Ask, when the account is opened, who approves and which address a follow-up quote should go to.
Factually, on the customer's agreement and the record of it:
IZZI DEVIS is software for professionals: it produces your documents and tracks your workshop, it collects nothing from your customers. See the IZZI DEVIS garage management software.
No. The DGCCRF fact sheet on unsolicited supply states that a consumer's failure to reply does not amount to consent, and article L121-12 of the Consumer Code prohibits demanding payment for goods or services that were not the subject of a prior order. Leave a message, send something in writing with the amount and the new timescale, and wait for the answer. If the vehicle tying up a ramp becomes the problem, renegotiate the timescale rather than assume the agreement.
Article 1366 of the Civil Code gives an electronic writing "the same probative force as a writing on paper", on two conditions: that the person it comes from can be duly identified, and that the document is established and kept so as to guarantee its integrity. An email sent to the customer's recorded address and kept on their file meets those conditions better than a screenshot. Above an amount set by decree, article 1359 requires a writing in any event.
No form is imposed: neither a quote nor a repair order is mandatory for vehicle repair. What counts is proof of what the customer ordered. A follow-up document listing the added lines, the total including VAT and the new time off the road is enough, provided it is dated and accepted. Reissuing the whole quote as a new version has one advantage: the customer sees the real total they will pay.
Only if those charges were known to them before they committed, through displayed prices and, ideally, a line on the repair order. In June 2026 the DGCCRF noted the recurring absence of displayed prices for diagnostic, storage and labour charges, even though they are invoiced as a matter of course. A charge that was never announced is a charge open to challenge.
The DGCCRF states that where the quality of the work or the amount of the invoice is disputed, the customer must pay to get the vehicle back, noting reservations on the invoice and its duplicate. On your side, produce the signed repair order, the accepted quote and the written record of the additional agreement: that file, not the argument at the counter, is what decides the matter if it goes further.
This article is general information, up to date as of 12 November 2026. It does not replace advice from your accountant or legal adviser.
The IZZI DEVIS team
Designs and builds IZZI DEVIS, the voice-driven workshop management software for independent garages.
Not mandatory, but it is your only written proof of what the customer asked for. The six details the DGCCRF expects and the value of the repair order in a dispute.
Prices including tax, labour rates, invoiced services, reused parts, ombudsman: the list, the texts and the penalties.
The texts, the three conditions, what retention allows, storage charges and price display.
When payment falls due, late payment interest, the EUR 40 indemnity, the reminder, the formal notice, then the recovery routes.
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