If they feel like their is mold although someone has already inspected for that ... you can get one of those water scanner things (sorry I have no clue what it is called) but it essentially checks for moisture (it shows certain color based on the moisture) also I would remove the base boards and cut about a foot of the dry wall to see if that is wet.

Furthermore, bad installation of siding seems to be more common than not and results in damage to the structure over time from water and moisture infiltration. the best part is, you don't know it until it's beyond a simple fix because all that lovely plastic siding is hiding telltale indications of problems.

(from our core rental agreement)Mold may grow and exist in any structure where there is, or ever has been, a presence of moisture and a food source for mold to grow.Its presence may exist without the knowledge of the structure owner and may be concealed from the untrained observer.Some varieties of mold are toxic and may cause adverse reactions in certain individuals.Tenant and Landlord will complete a Mold and Moisture Hazards addendum that will become part of this rental agreement.MOISTURE AND MOLD.

Here in PA, the disclosure form specifically states ‘do you leave knowledge of...’With that wording, it’s hard to say you (she) doesn’t have knowledge of moisture/water problems.

He’s put in tile and LVP floors so no carpet to clean or replace, the bathroom lights are wired with automatic fan turn-on which prevents moisture accumulation resulting in mold, etc.  

Add in water/moisture sensors, etc and you could have a fully-wired house sending you alarms to allow early intervention to what could become major issues.

The first time we did it, we had the other sides of the shower wall studs all exposed, ran the shower for several hours to watch for any signs of moisture, and saw nothing. 

Install new Housewrap weather and moisture barrier.

How's the roof, foundation, moisture and neighborhood?  

For moisture... bring with you a moisture meter.