The family has now turned their sites to the home inspector and real estate appraiser. They plan on suing both of them. To do this they have retained an attorney who previously specialized in asbestos related cases, who just happens to be a Philadelphia lawyer. Avoiding liability is simple. You need only a rudimentary understanding of mold.
All mold needs to grow is moisture, a little heat and some food.
If chronically wet material is part of the mold equation, you must first recognize the conditions that can allow moisture to enter the structure. It is not your responsibility to recommend testing, although doing so can help reduce your liability. If you are a home inspector you need to report the conditions and recommend mold testing. Frequently, all of the above-described conditions are readily observable, if you look for them. Missing them is inexcusable.