I'll start: Handheld FLIR TG267 thermal camera for detecting water leaks is 20% off at Amazon.

High-quality fake IDs that cannot be detected by the naked eye are readily available to criminals.

I was told that the sewer lines from the house to the street can possibly get clogged / or damaged by tree roots which is impossible to tell during a home inspection unless a sewer line camera is ran down the sewer line to detect the problem.

Also, with certain meters it can also help you detect leaks proactively, which really helps too.

You would have to factor not just a plumber to fix the leak but perhaps a contractor to repair the dry wall and 2 by 4s or even pest control to detect if there were termites.

Someone broke off the combination lock from our iron gate and came in directly through the doors of our rehab property, taking 4 bags of our contractors tools, to top it off ADT alarm system did not detect any motion what so ever in the property!!!

Rather than spending time finding and closing real estate deals - I have to set aside blocks in my day to perform detective work because Marcus Mullings made a conscious and premeditated decision to cheat me out of thousands of dollars.

Most with a true service animal are delighted to brag about their dog's special skills (seizure or low blood sugar detection, balance, etc). 

Some very clever detective work of some sort.

I still don't know how to detect deception from a seller but given that evictions are going to start up soon maybe that is less likely to happen.