Journal
What a USPAP fine art appraisal report includes
A letter with a number is not a report. Intended use, definition of value, identification, comparables, and a signed certification are the parts that get read later.
A USPAP fine art appraisal is a written opinion of value that shows how the number was reached. A one-page letter stating a figure, without scope or certification, is not a report an insurer, the IRS, or a court can rely on.
The skeleton
A report that follows USPAP states intended use and users, the definition of value and effective date, the scope of work, identification of the property, analysis of the relevant market, the comparables, any extraordinary assumptions, and the appraiser signed certification.
Insurance reports typically organize objects to Getty Object ID and state retail replacement value. Donation and estate reports state fair market value.
Why the certification matters
The certification states there is no interest in the property, that the fee is not contingent on the value, and that inspection occurred as described. Limiting conditions stay in the document so no one later pretends the report said more than it said.