Another rule is to respect people's privacy. One idiot in the Urbex community on Hive would post photos of the former occupants' ID documents and clear photos he found lying on a table in a house that he had explored. He calls himself an elite urban explorer. His photos are mediocre at best.
Technically, exploring a building or a property lot without permission is trespassing and grounds for criminal charges. The very least one can do is to show utmost respect to whatever place one is exploring, including the privacy if its owners or former occupants if it's a home.
RE: Exploring an Old Derelict Quarry and Outbuildings