Motivated seller and agents

If a motivated seller calls an investor who happens to be a real estate agent is there a problem? Lets say that they are willing to give it away at 60% of fmv. If I disclose that I am an agent and am not there representing them, is it fair game? Or what if one of the members of the llc that is buying the property is an agent, but not the one negotiating and signing the paperwork? Does that have to be disclosed, and does it mean you are obligated to tell them what it is really worth?