Expensive Doctor

A young woman wasn't feeling well, and asked one her co-workers to recommend a physician. "I know a great one in the city, but he is very expensive. Five hundred dollars for the first visit, and one hundred dollars for each one after that." The woman went to the doctor's office and, trying to save a little money, cheerily announced. "I'm back!" Not fooled for a second, the doctor quickly examined her and said, "Very good, just continue the treatment I prescribed on your last visit."