There is no reason to. This is one of the most neglected yet important steps in the submission process. Courier is the industry standard font style and the font size should be no less than 12 point. If your script exceeds 150 pages, pare it down. Cheated margins are very obvious.
Brass brads are the binding of choice.
Conformity rules when it comes to how your script looks. Send only the script or manuscript. Save your money for more copies. Depending on the volume of submissions during a given time, it should take between 2 to 4 weeks. Many people get caught up on the buying trends of Hollywood when in reality, it doesn't matter.