All appraisals must be in accordance with Sec. 4279.144 and each appraisal must be a complete, self-contained appraisal. Lenders must complete at least a Transaction Screen Questionnaire for any undeveloped sites and a Phase I Environmental Site Assessment on existing business sites in accordance with ASTM International Standards, which should be provided to the appraiser for completion of the self-contained appraisal. Specialized appraisers will be required to complete appraisals under this section. The Agency may approve a waiver of this requirement only if a specialized appraiser does not exist in a specific industry or hiring one will cause an undue financial burden to the borrower. Sec. Sec. 4279.245-4279.249 [Reserved]