What ever happened to saying "You don't match your pictures. Sorry, but both of our times have been wasted. Please leave." when you open the door or look through the peephole? Just because someone shows up doesn't mean you have to engage in their services. A person still has the right to say, "Not today, thanks."
(ah, the wonders of relying solely on the internet to try to find a guy....you don't know for sure what you're getting until they're at your door.)