How to treat a new sales representative. A typical complaint by dentists is that they like their old representative better. That may be true if the new representative is not as highly trained, or experienced. The key is to let the sales representative know what you would like to learn and ask them next time to be prepared to answer certain questions in a polite manner while developing a great relationship. They will go out of their way to be of help to you or put in touch with someone who can answer your questions.