# How do I correct one estimate line without losing the scope?

> Follow an eight-to-six quantity correction, check the $90 difference and preserve the deposit, timing and exclusion that did not change.

[Canonical article](https://makethisuseful.com/articles/estimate-correction-example)

By Make This Useful. Published 2026-09-09; updated 2026-09-10.

Prepared with AI assistance. Worked examples are original fiction, not customer records or professional findings.

![Match scope before comparing totals. A written exclusion and an unanswered question stay visible beside the supplied price.](https://makethisuseful.com/articles/media/estimate-compare.svg)

Original explanatory diagram. Match scope before comparing totals. A written exclusion and an unanswered question stay visible beside the supplied price.

Correct an estimate by identifying the changed source value, recalculating the affected amount and preserving the commitments that were not changed. A new quantity does not automatically revise a deposit, completion window or exclusion.

Our fictional small repair estimate uses US dollars and explicitly supplied quantities. The example checks arithmetic only; it does not determine the quantity the job requires.

## The original estimate

| Supplied row             | Arithmetic        | Amount |
| ------------------------ | ----------------- | ------ |
| Eight panels at $45 each | 8 × $45           | $360   |
| Labor                    | Stated amount     | $420   |
| Disposal                 | Stated amount     | $60    |
| Total                    | $360 + $420 + $60 | $840   |

The fictional document also states a $200 deposit, a proposed two-day completion window and painting excluded. Its tax treatment is not stated. Preserve those details beside the calculation so a reader knows which commitments the amount accompanies.

## Apply one confirmed correction

The author supplies: “Six panels, not eight. Keep the unit price and everything else.” The panel row becomes 6 × $45 = $270. The revised total is $270 + $420 + $60 = $750. The decrease is $90, exactly two panels at $45.

The $200 deposit remains $200 because no replacement amount or percentage rule was supplied. The proposed two-day window and painting exclusion also remain. The output still says “tax treatment not stated.” Correct arithmetic cannot fill an absent term.

## The finished revision note

> **Repair estimate — revision 2**
>
> Changed from eight to six panels at the author's request. Unit price remains $45.
>
> Panels $270; labor $420; disposal $60. Revised total: $750. Reduction from revision 1: $90.
>
> Deposit remains $200. Proposed completion window remains two days. Painting remains excluded. Tax treatment is still not stated.
>
> **Before use:** Check the revised quantity and retained terms against the current source estimate. Obtain the intended recipient's review through the normal channel.

If a balance after deposit is useful, it is $550 only on the condition that the $200 deposit applies against this $750 total. Do not describe it as money already paid unless payment was actually reported. “Deposit requested,” “deposit paid” and “remaining amount” are different facts.

The [FTC's guidance on written estimates](https://consumer.ftc.gov/articles/how-avoid-home-improvement-scam) supports keeping the work and terms available for review. This example's edition and correction method are original, and the app does not send an estimate merely because you inspect it.

[Review your own estimate](https://makethisuseful.com/start/estimate-grader). Choose the checklist answers yourself and enter the current labor, materials, other charges and total. Keep this article's quantity calculation with your source; the tool checks the entered amounts and prepares questions, without reading or correcting the original estimate.

## Use this with your own information

[Check my estimate](https://makethisuseful.com/start/estimate-grader)

The tool works without an account. The example's people and values are not transferred to your work.

[Download the estimate comparison and questions sheet (text)](https://makethisuseful.com/articles/downloads/estimate-compare.txt)

## Sources and this edition

Original fictional examples reviewed for supplied facts, arithmetic, unknowns, source attribution and a usable blank-tool destination. This is an editorial check, not an inspection, clinical review or professional endorsement.

- [FTC: How to avoid a home improvement scam](https://consumer.ftc.gov/articles/how-avoid-home-improvement-scam): The FTC recommends several written estimates and checking work, materials, completion timing and price. Our amounts and comparison decisions are constructed examples, not market prices or legal advice. Checked 2026-09-09.

September 10: clarified the guided self-assessment interaction and task-specific takeaway. All people, prices, items and household situations in the worked examples are fictional. Their facts are not transferred when you start your own tool.