"Trying to verify" is what he's supposed to do. Check what they have vs his other data sources and decide which - if either - he thinks is sufficient to use. Same as if the data sources said it was 900sf but he could see on a 2055 that it's clearly larger.
Nor is he supposed to be trying to use disclaimers to get out from under the obligation to reconcile for his choice to believe one over the other. There are conditions that apply to the use of an assumption:
View attachment 107092
If he can't articulate why he thinks one is usable and the other isn't then he shouldn't be making an assumption that it is. The term
"to the best of my knowledge and belief" has a distinct meaning that he either actually means or doesn't mean.
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Nobody thinks (or cares) that the no-look is somehow better for the appraiser. That was never the question and never the motivation. The question is what the user who is accepting these thinks is nominally sufficient for their usage.