When you are asked by an outside group for a tour of your facility, don't think of it as a marketing activity. Instead think of the audience. Who are they? What will help them solve their problem? Why did they pick your facility?
Do they really need to know how many trauma surgeries you did last year, or do they need to tour your trauma department and talk to the surgeons and nurses? Do they really need to endure the standard dog-and-pony PowerPoint program or do they need the time to have a robust Q&A...not with your CEO or CNO, but rather your most endearing ED nurse?
Be careful when you are asked for the tour. Find out first what your visitors want.