Letting one's paranoia run amok may not be the best approach. I can not believe every real estate agent is not aware of the dangers of going ANYWHERE or doing ANYTHING --- ALONE!
It has been my experience that if those you are dealing with understand others know you are with them, they fully realize they are not unknown and can be found. If I choose to respond to a 'curb side' call, I will make certain the buyer overhears me report via cell phone that I am currently with, "Bod and Sue Smith, license # b1b 2m2 (FL-Pinellas)." The only comments I've ever heard was, "We're so glad you take precautions to keep safe."
When it comes to open houses, we simply have to stop doing those old fashioned ones. When conducting an Event Open House,I let attendees know when they walk in, the only purpose of the open house is to allow the visitor to decide if they want to schedule a more complete showing. PERIOD. No, there is no wandering around, opening cabinets or drawers. They are with event staffers and are shepherded through the home. 15 minutes and they are out! After all, how long does it take to know if the home is too big, too small or outside of their price range? It is at the event station or tent that all the real magic takes place. Open Houses, using this concept, are never conducted alone.