Go with the market standard for the area.
Many many many of those old homes gained a bit of sq ft by calling the front and rear sunrooms or porches, GLA, after modest adjustments.
If it's got heat, electricity, and general insulation; it's GLA.
If it's not recognized as GLA via county, that makes your job easier to just call it a sunroom.
You only head and shoulders attic. But in all practicality; that means you stick your camera up or down, and take pictures.
Only now and then do I jump into a crawl or go up into an attic. Usually the pics from the opening is all you need.
What would you hope to find in inspecting this area? Probably a bunch of dirt. You're more likely to find junk, asbestos, and who knows what else, in a primary crawl area. For a small area with no access, that's a tough call, but one which probably would not stop the process. Assuming there is still that upper wall separating the rooms. Now if they took the wall down and put this area over mixed foundations, that's a difficult issue which could have problems. Not likely though. Most likely is they just enclosed the porch, and called it GLA. As long as they have flooring covering, heat, and electricity, it's probably no biggie, but has reduced contributory value compared to actually properly developed GLA additions. You'll probably find this condition is quite common, and your comps have similar appeals which are recognized as GLA. Therefore; assume, disclaim, move on. Put a note that you reserve the right to change your opinions, as the inspection was completed for HUD, but the HUD offices were closed due to government shut down. Easy outs.
