A lot of panic about a lot of nothing. I keep repeating that 4000.1 is almost the same as 4150.00.
I started FHA 20+ years ago and head & Shoulder inspections, crawl space, operating mechanical equipment, peeling paint on pre-1978 homes, loose wiring, testing a sample set of electrical outlets, turning on the water flushing toilets, observing the roof from the ground for evidence of missing shingles , looking at interior ceilings for evidence of water stains due to a leaking roof , reporting external issues like rail road tracks, power lines, airports or being located adjacent a gas station. ** Nothing New.
Use some common sense FHA/HUD does not require you to crawl under the house or walk on rafters when there is no supportable floor. A finished attic with floor then yes you may enter and observe. If not stick your head in the scuttle and with a large flashlight look around the best you can and take some photos, if you see something weird like loose wires, a dead body or a hole in the underside of the roof then report it. Look in the crawl space with your flashlight and take some photos. If you see evidence of water leaking from pipes underneath or water draining under the home call it out .
Call your local HOC if you are not sure and explain the situation because the appraisers are fairly nice and most of the time they will tell you to observe what you can physically. They do not expect you to walk on a rafter or 2 X 4 and fall through the owners ceiling. Write down the day and time of your conversation and document it in your work file.
In Summary: Nothing has really changed it's just many newer appraisers may have not been doing FHA properly for a long time and many never read 4150.00 or took a class. It was easier back in the day because FHA required us to use VC sheets ( valuation condition ) the form walked you step by step through the property with check boxes with questions about electrical , peeling paint, termites etc.