When doing a home inspection here in the Los Angeles area, I find the attic is an essential part of the story of a house. The attic holds facts that are not always evident in the rest of the house.
Attics are actually a point of debate in the home inspection industry. The standards of practice issued by ASHI, CREAI and InterNACHI all state the inspector does not actually have to enter the attic. There are some home inspector who actually do not enter and inspect the attic.
At IM Home Inspections, I feel it is essential to enter the attic, unless there are reasons not to, such as the attic space is too small to crawl around, or the temperature in the attic space is excessively hot.
Even in very nice houses, with updated luxury kitchens and all the trimmings, the attic can tell a different story. I have seen gorgeous houses where the attic had rodent droppings. I have seen houses that were newly remodeled, yet the duct work in the attic was disconnected. Most recently, I found a hole in the roof that was under the roofing tile, in such a way the hole was not visible from the top of the roof itself. All of these things could not be discovered if I did not enter and inspect the attic.
When hiring a home inspector, make sure you hire a qualified professional who will take the time to get the whole story about your house.