Does Home Sale Imply Photo Permission?

Dear Rich: So, is an agent who is helping a buyer, who is not trespassing, who is invited into a home for sale (via a Realtor's ad), allowed to snap photos and publish them online for all to see, without specific expressed permission? Or is the permission implied with allowing 100+ buyers into the vacant home? Or is it a conditional invitation with limitations on rights to photograph? Just because you were invited on to someone's property, vacant or not, does not imply the right to take photos. The best argument you could make would be that the seller or the seller's agent was aware of you taking photos and didn't complain. (For example, the Dear Rich Staff was recently at the Google offices in San Francisco, taking a video of the free lunch -- it was pretty impressive stuff, gourmet pizza, fresh broccoli, incredible salads, and free wheat grass juice in these little shot glasses - until a Google rep explained that no photos were permitted. Okay we got the point even though we still like looking at the video when we're hungry.)  The next question is whether permission is required. After all, permission is only needed if you are violating someone else's rights. Someone may claim your posted photos violate copyright law -- a long shot -- assuming there's something copyrightable in the photos (artwork on the walls?); or someone may possibly claim invasion of privacy (although if the house is vacant and hundreds of people are walking through it, that's a tough argument to make). It may be a violation of contract if ads for the home state "No Photos." It may violate someone's right of publicity (wow, check out this cool right of publicity site) if you photo them in the house and you use that photo to sell the home, blah, blah, blah. The real issue is why are you asking this? Are you being hassled because you're an agent who showed up at a home for sale, took pictures, posted them without permission? If that's the case -- and since agents need to work together cooperatively in most communities (especially in a tough real estate market)  -- don't you want to work this out with the people you are dealing with on a day-to-day basis? It's always more satisfying to "get to yes" without bringing in the legal blowhards. (What's the movie poster got to do with your question? There are a lot of vacant homes for sale in New Granola.)