Never Split the Difference: Negotiating as if Your Life Depended on It by Chris Voss

This book will teach you how to take control in essential conversations in your daily life. Chris Voss is a former FBI negotiator, who often negotiated with kidnappers to free hostages. Once, kidnappers asked the family of a hostage to pay a ransom of $150,000. The family told Voss that they could pay between $50,000 to $85,000. However, Voss successfully managed to lower the price to $4,751, and the hostage was rescued safely.