Inspect the specific area of concern
The reported symptom should guide inspection of supply runs, returns, registers, and accessible air-handler components. Visible material at a grille does not by itself show how much ductwork is affected, so observations should identify where buildup is present. If images are used, they should correspond to the areas being discussed. This evidence helps distinguish a limited cleaning need from a broader scope and avoids treating every system as though it has the same condition.
