If the Appraiser observes additions or structural changes to the original manufactured home, the Appraiser must condition the appraisal upon inspection by the state or local jurisdiction administrative agency that inspects manufactured housing for compliance, or a licensed structural engineer may report on the structural integrity of the manufactured dwelling and the addition if the state does not employ inspectors.
For additional information see Handbook 4000.1 II.D.5.i. at https://www.hud.gov/program_offices/administration/hudclips/handbooks/hsgh