Appraisal reports are private, prior appraisals do not follow the house, and yes, a value can be formally challenged. Appraisals are not public record, and a new appraiser does not see prior reports on the home. Fannie Mae and Freddie Mac do maintain a proprietary database of appraisal data that feeds their appraisal-waiver models, but that database is internal and is not shared with appraisers or the public. Challenges run through defined processes: - VA loans use Tidewater. When the value looks likely to come in below the sales price, the appraiser must notify the lender's point of contact before completing the appraisal, and the parties then have two business days to submit additional sales data through that channel. - Conventional loans use a reconsideration of value. Fannie Mae and Freddie Mac standardized a borrower-initiated ROV process in 2024. You start it through your lender, you can submit up to five additional comparable sales plus factual corrections, and you get one ROV per appraisal. Loose disagreement will not move a value. Specific, documented evidence is what a reconsideration runs on, so work with your agent to assemble the strongest comparable sales before you file.