My parent's house had a crack in the foundation walls
I've had someone come through my house with a thermal imaging camera. It was to check for draft's, but the cameras can see through finished walls and show you where there are problems. The cameras will show mold or moisture behind drywall, insulation that has fallen (or lack of it), draft's around your house and in your HVAC, and even show hot spots or areas of concern in a fuse panel. The inspection isn't cheap, but it's well worth it IMO.
The gentleman that did the specific area of concern for me, came back with the results that included thermal imaging photographs with detailed information that was all put together in a small binder for me to keep (I still have it, and will gladly scan the results if it's of interest to anyone).
