A red flag on an appraisal report is anything the report cannot support from its own data: a fact about the house that does not match the record, a comparable sale from a different market with no explanation, an adjustment with no market evidence behind it, or a final opinion that does not follow from the analysis shown. A value lower than you expected is not a red flag by itself. In Claremont, a reviewer checks the facts of the house first, then whether the comparable sales came from the right pocket, then the adjustments, and treats each flag as a question to test against the data, not a verdict.
This article is for buyers, owners, agents, loan officers and attorneys holding a report they question. The wider set of options after a questioned report is collected in the low appraisals, reviews and second opinions hub.
What does "red flag" mean in an appraisal review?
An appraisal review is an assignment in which one appraiser develops and reports an opinion about the quality of another appraiser's work. It is governed by USPAP Standard 3, the part of the Uniform Standards of Professional Appraisal Practice that sets out what a reviewer must identify, examine and report. Inside that work, a red flag is a point where the report and the evidence part ways, and the reviewer has to find out why.
Some flags resolve on a second look. A comparable that seems far away may be the closest similar sale in a pocket with few sales, and the report may say so. Others hold up and become findings. The difference matters, because a review that treats every surprise as an error is no more credible than the report it is reviewing.
The clearest public list of what lenders treat as a problem is Fannie Mae's Unacceptable Appraisal Practices topic in its Selling Guide. It includes misrepresenting the physical characteristics of the subject property or the comparable sales, selecting inappropriate comparable sales, failing to use the sales most locationally and physically similar to the subject, using adjustments that do not reflect market reaction, and failing to make time adjustments when they are clearly indicated. It also names subjective terms such as "pride of ownership" and "desirable neighborhood", and any reference to a protected class.
What does a reviewer check first?
The order follows the report, because an error early in the report carries through everything after it.
- The scope. Does the report state its intended use, what it will be used for; its intended users, the people entitled to rely on it; its effective date, the date the opinion of value applies to; and its scope of work, the type and extent of research and analysis?
- The facts of the house. Gross living area, the finished, heated space above grade, along with room counts, lot size, year built, and permitted additions or ADUs. On older Claremont houses near the Village and the Colleges, porches and back rooms were often enclosed decades ago, so a living area copied straight from public records, with no measurement behind it, is the first thing to check.
- Comparable selection. Were the sales the ones a buyer of this house would have weighed, from the same pocket and the same era, and did closer matches close within the report's time frame?
- Adjustments. Is each adjustment for size, condition, view, lot, location or time explained and supported by market evidence, or simply applied?
- Reasoning. Does the final opinion follow from the adjusted sales the report shows, and does the report explain how it weighed them?
Which red flags come up most around Claremont?
These are the kinds of reports that come in for review, and the patterns a reviewer looks for. One ZIP code, 91711, holds several markets, so most local flags involve a comparable sale crossing a line that buyers notice.
- A sale across the county line with no adjustment. Cross Mills Avenue or Claremont Boulevard and you are in Montclair or Upland, in San Bernardino County, with a different assessor, different school districts and a different buyer pool. A Montclair or Upland tract sale used for a Claremont house needs a stated reason and a location adjustment. What the county line does to comparable sales explains why.
- A sale across the 10 or the 210. South of the 10 the stock shifts to later tracts, townhomes and condominiums. A townhome there used to value a detached house near the Colleges is a flag on its face.
- A hillside home compared with flat lots. Claraboya and Padua Hills homes sell on view, grade and access. A report that leans on flat lots below Foothill Boulevard with no view or grade adjustment raises the question.
- A pre-1940 house matched by bedroom count. A Craftsman or Spanish Colonial Revival house near the Village differs from a postwar ranch north of Foothill in lot, era, living area and setting. Matching the two on bedrooms alone is a common finding.
The Claremont area page describes these pockets and why comparables cross them only with stated reasoning.
What is not a red flag?
- A value below the contract price. The price is one agreement on one house; the appraisal is an opinion of market value drawn from several closed sales.
- A higher automated estimate, such as a Zestimate or another automated valuation model. An automated estimate is a statistical figure from records and nearby sales, and it is not an appraisal. The difference is set out on appraisal vs. estimate.
- An agent's CMA, a comparative market analysis of likely list or sale price, which is not an appraisal either.
- The county's assessed value, the taxable value under California's assessment rules, which is also not an appraisal.
- A distant comparable that the report explains. In Claraboya and Padua Hills the right sales often come from a wider foothill band, and a stated reason for the distance is exactly what a reviewer hopes to find.
What should you do with a flag you find?
Write it down with the evidence behind it: the permit, the measured sketch, the closed sale and why it is similar. Then pick the route. If a lender ordered the report, the route is a reconsideration of value through the lender, walked through in how to challenge a home appraisal through the lender, with the content of the request covered in what a lender considers in a reconsideration of value. The broader options on a purchase or a refinance are in what happens if the appraisal is low, and the choice between a review and a new appraisal is laid out in how to challenge a low appraisal: review vs. new appraisal.
For a lender appraisal, do not call the appraiser. Appraiser independence, the rule that a valuation must rest on the appraiser's own judgment and not on pressure from anyone with an interest in the loan, is written into federal lending rules at 12 CFR 1026.42. The same rule allows the lender to ask the appraiser to consider additional property information, explain a conclusion or correct errors. That is the channel a red flag belongs in.
A reviewer is independent of every party, including the one who orders the review, and may conclude that the original report is supported. If you want the report examined before deciding what to do, send it through appraisal review and second opinion or call (909) 324-6122. The fee is set by the scope of the assignment and quoted before work begins, and it does not depend on the value.
Sources
- Fannie Mae Selling Guide B4-1.1-04, Unacceptable Appraisal Practices: https://selling-guide.fanniemae.com/sel/b4-1.1-04/unacceptable-appraisal-practices (accessed October 30, 2026)
- Fannie Mae Selling Guide B4-1.3-12, Appraisal Quality Matters: https://selling-guide.fanniemae.com/sel/b4-1.3-12/appraisal-quality-matters (accessed October 30, 2026)
- Consumer Financial Protection Bureau, Regulation Z, 12 CFR 1026.42, Valuation independence: https://www.consumerfinance.gov/rules-policy/regulations/1026/42/ (accessed October 30, 2026)
- The Appraisal Foundation, Uniform Standards of Professional Appraisal Practice (USPAP): https://appraisalfoundation.org/imis/TAF/Standards/Appraisal_Standards/Uniform_Standards_of_Professional_Appraisal_Practice/TAF/USPAP.aspx (accessed October 30, 2026)
- Claremont, California (Los Angeles County; borders Upland and Montclair): https://en.wikipedia.org/wiki/Claremont,_California (accessed October 30, 2026)
- Montclair, California (Mills Avenue as the western boundary): https://en.wikipedia.org/wiki/Montclair,_California (accessed October 30, 2026)
Gordon Hall, California Certified Residential Real Estate Appraiser, BREA No. AR003877 (lookup: https://www2.brea.ca.gov/breasearch/faces/party/view.xhtml?id=23601). Reports are prepared in conformity with the Uniform Standards of Professional Appraisal Practice (USPAP). Nothing here is legal or tax advice; admissibility is always the court's decision.
Frequently asked questions
Is a low appraisal a red flag by itself?
No. A value below the contract price or below what an owner expected is not a red flag on its own. A red flag is a specific point the report cannot support from its data, such as a wrong living area, an unexplained comparable from a different market, or an adjustment with no market evidence behind it.
What red flags do appraisal reviewers find most often around Claremont?
The recurring ones involve comparable sales that cross a line buyers notice: sales from Montclair or Upland across the Los Angeles and San Bernardino county line with no location adjustment, sales across the 10 or the 210, flat-lot sales used for Claraboya or Padua Hills hillside homes, and postwar ranch houses used for pre-1940 houses near the Village on bedroom count alone.
Can I contact the appraiser about a red flag in my lender's appraisal?
For an appraisal ordered by a lender, questions go through the lender, not to the appraiser. Federal lending rules protect appraiser independence and allow the lender to ask the appraiser to consider additional information, explain a conclusion or correct errors, which is what a reconsideration of value does.
Does an appraisal review always find problems?
No. An appraisal review tests the report against the data under USPAP Standard 3, and the reviewer is independent of every party. A review can conclude that the original report is supported, which is useful information in itself.
