We check the roof deck and rafters for staining and soft spots, since that's where a roof leak shows up first. We look at insulation for compression, discoloration, or a musty smell, and we check whether bathroom and kitchen exhaust fans actually vent outside the attic instead of dumping warm, moist air into it. Misdirected bathroom fans are one of the most common causes we find in this area, and they're often an easy fix once identified.
Ridge vents, soffit vents, and gable vents all get checked too. Coastal Grand Strand attics run hot and humid for much of the year, and if the vent system isn't moving air the way it should, that trapped humidity condenses on the underside of the roof deck and gives mold exactly what it needs.
Recessed light fixtures and attic access hatches are worth a look as well. Both create small gaps between the living space and the attic, and warm, moist air from inside the house rises through them all day, adding to whatever moisture is already trapped up there.