> If you solved as many notes as I did you would understand ;) I think that photographing something that's not there is still a valid thing. I try never to trust notes blindly, and when possible corroborate it with outside sources (no copying of Google Maps allowed, though).

I think this can get tricky. I've worked in several office suites where having a business listed on the directory at the entrance was an additional fee that many tenants opted not to pay (not just struggling startups; I've known this category to include large publicly-traded companies who'd existed for decades). Someone could see that a listed business is not on the directory, mark "no longer exists", even posting "photographic proof" of a directory without the business's name -- and they could still be wrong.

The only way to know for sure would be to a) verify the landlord's records; or b) regularly knock and confirm that employees of said company are routinely occupying the space.