Here in the City of Geneva, Code Enforcement enters all rental properties every year under the guise of health and welfare.
The are allegedly looking for electrical hazzards, structural problems and working smoke detectors.
Last year I was present when the came by. The "inspector" took note of my gun collection and got very upset when I told him that none of his business and he needed to move along with his day (read - get to work and stop milking it.)
What part of the Fourth Amendment doesn't your city understand? Does the existence of smoke detectors negate "the right of the people to be secure in their ... houses?" These kinds of laws and regulations are perfect arguments for constitutional absolutism. Although I've never subscribed to that doctrine, the more I see of these compromises, the less ground I'm willing to give.