Sorry, I want to be 100% clear on what you mean, and I am not.
In the case cited (500 SF error in reported GLA), do you think that report would violate SR 2-1(a) or not?
STANDARDS RULE 2-1, GENERAL REPORTING REQUIREMENTS
Each written or oral real property appraisal report must:
(a) clearly and accurately set forth the appraisal in a manner that will not be misleading;
In your example, you were very clear that the error of 500sf was because an appraiser relied upon past measurement information, which was not current and didn't include an addition. The appraiser, in your scenario, did not measure the home upon his new inspection, and the subsequent report's opinion of value is simply inaccurate because the home's size was portrayed as being smaller in his appraisal.
The error was not caused by a malfunction in equipment, nor was he relying upon third party information in your example.
SR 1-1(b) states the appraiser
must not commit a substantial error of omission or commission that significantly affects an appraisal...... Goes on to discuss the required care in avoiding errors that would significantly affect conclusions. Discusses the diligence required, including identification and analysis of factors, conditions, data, and other information impacting credibility of the assignment results.
SR 2-1(b) states the appraisal report
must clearly and accurately set forth the appraisal in a manner that will not be misleading.
In the prior USPAP definitions page, "Misleading" was specifically defined as: "Intentionally or
unintentionally misrepresenting,
misstating, or concealing relevant facts or conclusions."
If you are asking if the failure of measuring a home in a new assignment, and utilizing prior information and presenting it as current, doesn't fall into the definition shown above, then I suppose we have different angles on the law.
One would say, the lack of a new measurement and using prior data as current is just a simple innocent error. Last I checked, an innocent error is synonymous with unintentionally misrepresenting or misstating facts, and I'm sure would be called misleading by those looking at the letter of the law based on the prior version definitions.
Is it a USPAP violation you asked? If that appraisal was used in court or reviewed by the commission due to a complaint from the seller, who lost money on the sale of his property because of that error, I suspect misleading would be the angle of argument. Don't you agree? (Did you just nod your head in agreement?)