Mold will generally form first around wherever there is water damage. We suggest starting around these areas for initial mold inspection and testing.
Once you discover mold in your facility it's important to keep in mind that mold travels very easily to surrounding areas. A simple way to think about it is mold will travel similarly to dust particles, therefore anywhere dust can go mold can go.
It is very important that if mold is discovered in an environment you treat the surrounding areas including contents and internal atmosphere in addition to the visible mold growth. The longer an environment is left untreated the stronger the risk of cross contamination into other rooms.
Often cross contamination occurs through the HVAC system, so we suggest treating the entire system if possible. There is a common misconception that bleach kills mold. When you apply bleach to a colony of mold spores it will wash out the color of the spore but not damage the spore itself.
The majority of mold spores are chlorine resistant making them immune to things like bleach. The only way to be sure to kill mold is to use products with an anti-fungal anti-microbial element properly applied.