The Uniform Standards of Professional Appraisal Practice otherwise known as USPAP are the quality control standards applicable for real property, personal property, intangibles and business valuation appraisal analysis and 
reports in the U.S. and its territories. USPAP was first developed in the 1980s by a joint committee representing the major U.S. and Canadian appraisal organizations and congress.
USPAP Standards Rule 8-3
Each written personal property appraisal report must contain a signed certification that is similar in content to the following form:
I certify that, to the best of my knowledge and belief:
— the statements of fact contained in this report are true and correct.
— the reported analyses, opinions, and conclusions are limited only by the reported assumptions and limiting conditions and are my personal, impartial, and unbiased professional analyses, opinions, and conclusions.
— I have no (or the specified) present or prospective interest in the property that is the subject of this report and no (or the specified) personal interest with respect to the parties involved.
— I have no bias with respect to the property that is the subject of this report or to the parties involved with this assignment.
— my engagement in this assignment was not contingent upon developing or reporting predetermined results.
— my compensation for completing this assignment is not contingent upon the development or reporting of a predetermined value or direction in value that favor the cause of the client, the amount of the value opinion, the attainment of a stipulated result, or the occurrence of a subsequent event directly related to the intended use of this appraisal.
— my analyses, opinions, and conclusions were developed, and this report has been prepared, in conformity with the Uniform Standards of Professional Appraisal Practice.
— I have (or have not) made a personal inspection of the property that is the subject of this report. (If more than one person signs this certification, the certification must clearly specify which individuals did and which individuals did not make a personal inspection of the appraised property.)
— no one provided significant personal property appraisal assistance to the person signing this certification. (If there are exceptions, the name of each individual providing significant personal property appraisal assistance must be stated.)
Comment: A signed certification is an integral part of the appraisal report. An appraiser who signs any part of the appraisal report, including a letter of transmittal, must also sign this certification.
In an assignment that includes only assignment results developed by the personal property appraiser(s), any appraiser(s) who signs a certification accepts full responsibility for all elements of the certification, for the assignment results, and for the contents of the appraisal report. In an assignment that includes real property, business or intangible asset assignment results not developed by the personal property appraiser(s), any personal property appraiser(s) who signs a certification accepts full responsibility for the personal property elements of the certification, for the personal property assignment results, and for the personal property contents of the appraisal report.
When a signing appraiser(s) has relied on work done by appraisers and others who do not sign the certification, the signing appraiser is responsible for the decision to rely on their work.
The signing appraiser(s) is required to have a reasonable basis for believing that those individuals performing the work are competent. The signing appraiser(s) also must have no reason to doubt that the work of those individuals is credible.
The names of individuals providing significant personal property appraisal assistance who do not sign a certification must be stated in the certification. It is not required that the description of their assistance be contained in the certification, but disclosure of their assistance is required in accordance with Standards Rule 8-2(a), (b), or (c)(vii), as applicable.
To order a USPAP compliant diminished value appraisal, please start by filling out this questionnaire:
