Put it into your own words and note what and why it could not be inspected.
Snow, ice, water, temperature, debris, fresh paint on foundation, wall & ceiling cover, utilities being turned off, locked doors, owners or tenants refusing access, furniture, stored items, animals, flea infestation, sealed access doors, too small or blocked access, broken glass in crawlspaces, & clothes in washers/dryers are just a few of the examples that I have prevented me from completing full inspections.
If there is a new Corvette parked under the attic hatch in the garage, that would be a restriction from accessing that attic space. I report the restriction as to the reason why the attic space was not inspected in the report and always include a picture.
Jeff’s got a nice list and Kevin beat me to it, I was thinking of the 68 Camaro sitting under the attic access, also hornets nest(s) or anything that keeps you from SAFELY performing the inspection. Safety first.
I went a little more vertical with the ladder than normal, to help reduce diagonal “flex.” And, I also opened the cover very, very slowly. If there was any sign of items coming out, it was going to stop right there.