Read the estimate before you say yes

How do I understand a car repair estimate?

Two questions that feel like one

Standing at a counter with an estimate, the question in your head is usually “is this a rip-off?” It feels like a single question. It is two, and they have very different answers.

The useful move is to answer the first question properly, then take that to the second — because “why is this part $X” is a question a shop can answer, and “does this feel like a lot?” is not.

What to do, in order

1. 1.Separate parts from labour before anything else

   These are priced completely differently and are worth questioning in different ways. A parts-heavy estimate and a labour-heavy estimate for the same total are not the same job, and knowing which one you are holding changes what you ask next.

2. 2.Check that the pieces add up to the total

   Subtotal, tax and fees should reconcile with the number at the bottom. When they do not, that is not automatically wrong — a discount, a shop fee or a rounding rule can explain it — but it is a specific, answerable question rather than a vague unease.

3. 3.Find the line you do not recognise

   There is almost always one. Shop abbreviations are written for the shop, not for you. Identifying which line you cannot read is more useful than trying to judge the whole document at once, because it turns "I do not understand this" into one clear question.

4. 4.Ask what that line is for, specifically

   Not "is this fair" — a question nobody on either side of the counter can answer from the paper — but "what does this part do, and why does this job need it?" A shop that can answer that quickly is telling you something useful. So is one that cannot.

5. 5.Keep the estimate

   Whether you approve it, decline it or take it elsewhere, the document is a record of what you were quoted and when. That matters if the work is done later, done differently, or quoted again by someone else.

What the app reads off the page

You can do all of the above with a pen. Kaiju Mechanic does the tedious part — photographing the estimate and turning it into something structured you can read.

Each piece comes with a confidence level, because a photograph of a creased carbon-copy is not always legible and it is better to say so than to quietly guess. You can then ask about a specific line in chat rather than re-typing the whole thing.

Where this stops

It does not tell you what to decline, and it does not benchmark the price. Both would require things the document does not contain — what the shop found that is not written down, how long you plan to keep the car, and what labour rates are where you live.

What it changes is that you walk back to the counter having read the thing you are signing. If the estimate followed a warning light, it is worth knowing what the diagnostic fee bought you as well, and what the code itself does and does not say.

Common questions

How do I understand a car repair estimate?

Start by separating two questions that feel like one. The first is what you are being asked to approve — which parts, which labour operations, which fees, and how they add up to the total at the bottom. The second is whether that price is reasonable. Only the first is answerable from the piece of paper in your hand, and it is the one most people never get to, because an estimate is usually a column of abbreviations and a number. Getting it broken into parts, labour, fees and tax — and confirming those pieces actually sum to the total — turns an approval you are guessing at into a conversation you can have.

How do I know if a repair estimate is fair?

This page will not tell you, and neither will the app — deliberately. What a repair "should" cost depends on your region, the shop, the vehicle, parts availability and labour rates, and we have no authority for a number that would survive being checked. What we can do is make sure you know exactly what is on the estimate before you decide: the breakdown, whether it adds up, and what each line is for. That is a real answer to a narrower question, and it is worth more than a confident answer to a broader one that nobody can actually support.

What does the app actually read off the estimate?

The totals — subtotal, tax, and the split between parts and labour — plus each line item with its description, quantity and price, and whether a line is a service, a part, a fee or tax. It also checks whether those pieces reconcile with the total, and it records the shop details on the document. Each piece carries its own confidence level, because a photographed estimate is not always legible and pretending otherwise would be worse than saying so.

Do I need an OBD-II adapter to use this?

No. This is the one thing in the app that needs no hardware at all — no adapter, no OBD port, and the car does not need to be present. You are scanning a piece of paper. Everything else in Kaiju Mechanic that reads your vehicle does need an adapter; this does not.

What do I need set up before I can scan an estimate?

Three things, and it is worth being straight about them: the app installed, an account (scanning is not available to anonymous users), and a vehicle added to your garage — the scan attaches the document to a specific car. None of that costs anything, and the free plan includes a few scans a month. It is a few minutes of setup rather than a single tap, which is why we would rather say so here than have you find out at the counter.

Can it tell me which items to decline?

No. Deciding what work to authorise depends on things the document does not contain — how long you plan to keep the car, what you can spend, what the shop found that is not written down, and how urgent each item is. What you get is a clear view of what is being proposed, so that decision is yours to make with the facts in front of you rather than a total you are nodding at.