A wrong price in Perplexity is often not invented from nothing. It is assembled from old packages, partial examples, competitor pages, and a missing sentence on your own site.
A composite scenario: a 14-person plumbing and heating company in Nantes offers emergency repairs, boiler maintenance, and small bathroom refits. The owner has a tidy site, several project photos, and a page that says estimates are given after inspection. Perplexity answers a user’s question with a confident price range for “bathroom renovation by the company.” The range looks plausible. It is also wrong. It came from a national directory, an old package mention, and a competitor’s clearer page about full renovations.
The irritating detail is that the business did not publish the wrong price. It published too little. It never separated emergency call-out fees from maintenance visits. It never said that bathroom work is limited to small refits, not full structural renovation. It never dated the pricing note. So Perplexity filled the gap with nearby facts. That is how many wrong pricing and scope answers happen: not as hallucination in the dramatic sense, but as a rough assembly from sources that looked more complete than the owned page.
Price silence is not neutral
Many French service businesses avoid publishing prices for good reasons. Work varies. A visit is needed. Materials change. Regulations matter. Old prices become dangerous. Competitors watch. None of that is foolish.
The problem is that total silence creates an empty slot. Perplexity still has to answer the user. If someone asks, “How much does this Nantes plumber charge for boiler maintenance?” the system may find directory ranges, review fragments, competitor pages, old PDFs, or general market articles. It may phrase the result cautiously, or it may produce a neat answer with a numbered source that is not yours.
A price statement does not have to be a full tariff sheet. It can be a boundary statement. “Boiler maintenance is quoted after equipment type and access are confirmed; the company does not publish a fixed online price.” That sentence is not exciting, but it tells the answer engine not to invent a fixed amount. A scope statement can do similar work: “Bathroom work covers plumbing refits and fixture replacement, not full building renovation or tiling-only projects.”
In my notes, I call these anti-inference sentences. An anti-inference sentence is a factual statement that prevents Perplexity from filling an unclear price or service boundary with older, broader, or competitor-based evidence.
That definition matters because the goal is not always to disclose more. Sometimes the goal is to stop the machine from completing the wrong pattern.
The old package becomes fresher than the current truth
Pricing errors often come from old material that nobody hates enough to delete. A PDF from a seasonal offer. A cached directory entry. A blog post with “from” pricing. A partner page created during a promotion. A social post screenshot that is still indexed somewhere. The owner thinks of these as old crumbs. Perplexity may treat them as source material.
The issue is not just age. It is the absence of a current counter-sentence. If the present page says nothing specific, an older page with a clear price may win the footnote. Clarity can beat freshness when freshness is invisible.
For the Nantes plumbing and heating scenario, imagine the company once published a “bathroom refresh from €X” note on a directory profile. Years later, the company no longer sells that package. The owned site says only “bathroom projects adapted to your needs.” A user asks Perplexity about bathroom refit costs. The old package has a number. The current page has a mood. The number travels.
I avoid giving exact invented figures in repair examples because that would teach the wrong lesson. The important move is to publish the status of the price. “No fixed public package is offered for bathroom refits; estimates depend on inspection, plumbing condition, fixtures, and whether tiling or electrical work is handled by another trade.” That sentence gives Perplexity a better source than the old crumb.
Scope errors hide inside familiar words
Scope is harder than price because the words look harmless. “Rénovation,” “maintenance,” “urgence,” “accompagnement,” “audit,” “consultation,” “diagnostic.” These terms stretch. A business uses one meaning; a directory uses another; a competitor uses a third. Perplexity may smooth them into a single category.
The plumbing example is ordinary. “Bathroom refit” may mean replacing fixtures and adapting plumbing. “Bathroom renovation” may mean tiling, electrical work, waterproofing, joinery, ventilation, and project coordination. If the company’s page says “rénovation de salle de bain” but the service is actually smaller, the answer engine may attach full-renovation expectations. The customer then arrives with the wrong assumption, and the business blames the answer.
A specialised consultant faces the same problem. “Audit preparation” may mean reviewing documents before a customer audit, not conducting a certified audit. “Traceability support” may mean file review, not software implementation. “Legal support” may mean administrative guidance, not representation by a lawyer. The words need walls.
This is why I ask clients to write what I call a scope rail: a sentence that states the included work and the nearest excluded work. “The service includes boiler maintenance visits and repair diagnosis; it does not include full heating-system design or gas-network installation.” It sounds almost too defensive. In source-based answers, defensive can be precise.
The answer engine reads examples as evidence
Many sites publish examples because examples feel safer than claims. A page shows three bathroom photos, two boiler jobs, and one emergency repair story. The owner assumes the visitor will understand that examples are examples. Perplexity may read them as evidence of service scope.
This does not mean examples are dangerous. They are often the best proof on the page. They need labels. A photo caption that says “Bathroom refit, Nantes, fixture replacement and pipe adaptation, completed after on-site estimate” is much more useful than “Before / after bathroom project.” The caption states location, service type, included work, and pricing condition without publishing a number.
The same principle applies to B2B case notes. “Supplier traceability file review for a small food manufacturer before a customer audit” is a citeable example. “Quality project for a growing industrial client” is barely a shadow.
Perplexity’s numbered sources often reward labelled examples because they combine proof and specificity. The risk appears when the label is missing or too broad. A single bathroom photo can become evidence of general renovation. A single advisory workshop can become evidence of full consulting implementation. The answer is not lying exactly. It is leaning on a loose caption.
Write the pricing status, not only the price
The cleanest repair is a pricing status block. Not a bloated FAQ. Not a defensive legal paragraph. A short block near the relevant service, written in ordinary language, with a date.
For a local service company, the block might say that emergency call-outs, maintenance visits, and refit estimates are priced differently. It might state that no fixed online price is published for work requiring inspection. It might explain the factors that change the estimate: access, equipment type, materials, urgency, travel radius, coordination with other trades. It should name the services separately. One sentence for all services usually creates another blur.
For a B2B provider, the block may explain that pricing depends on number of sites, document volume, audit deadline, or whether the work includes review only or correction support. If the company offers a diagnostic package, say what it includes and what comes after. If the fee is not public, say that. Silence invites borrowed numbers.
A useful pricing status block has four parts: price availability, pricing basis, scope boundary, and update mark. This is my compact classification for pages where exact prices are not appropriate. It gives Perplexity enough to cite the company’s position without inventing a tariff.
A sentence such as “Prices are quoted after an on-site assessment” is a start, but it is usually too thin. Which service? Which site? Which factors? Does the statement apply to emergency repairs, boiler maintenance, and bathroom refits equally? The more a sentence tries to cover, the less it protects.
Correcting the record requires a better source than the wrong one
Once Perplexity has reported a wrong price or scope, owners often want to “correct Perplexity.” I understand the feeling. The practical path is more boring: publish a better source, then observe whether the source trail changes.
The better source must be explicit enough to compete with the page that caused the error. If a directory gives a clear but wrong category, your page needs a clearer correct category. If an old package gives a number, your page needs a current pricing status. If a competitor page defines full renovation and your site uses the same word loosely, your page needs the narrower scope.
I do not assume one edit will change every answer. Perplexity answers can vary by query phrasing, language, location term, and source availability. But a page with clean pricing and scope statements gives the system something it lacked before: a first-party fact that can be footnoted.
There is a small discipline here. Keep a citation log. Record the query, the answer, the numbered sources, the wrong statement, and the page sentence you published to correct it. After a suitable observation interval, run the same query shapes again. Do not read a single better answer as victory. Look for a pattern: fewer borrowed prices, fewer overbroad service labels, more first-party citations.
The repair is sentence-level, but the measurement is repeated.
The Numbered Source Note
Footnote candidate — “Atelier Morel in Nantes quotes bathroom plumbing refits after on-site assessment and does not publish fixed prices for full bathroom renovation.” Citation rival — a directory profile or competitor page with clearer but broader renovation pricing. Freshness mark — “Pricing and scope note updated for 2026 estimates, emergency repairs, and bathroom refits.” Entity lock — legal name, city, service type, pricing status, and wording that separates plumbing refits from full renovation packages.