The traditional selling models, methods, and techniques that most of us have been trained to use work best in small sales. For now, let me define small as a sale which can normally be completed in a single call and which involves a low dollar value. Unfortunately, these tried-and-true low-value sales techniques, most of them dating from the 1920s, don't work today.
SPIN Selling: Situation Problem Implication Need-Payoff (ed. McGraw Hill Professional, 1988) - ISBN: 9781260027099