How to Win Friends and Influence People, by Dale Carnegie, has got to be rated A+.
This book is simply amazing. Reading this is like looking behind the curtain in the Wizard of Oz. Carnegie reveals how people work, think and act better than anyone we've ever read. His courses are still taught today, decades after this book was written. We often give this book to anyone getting into real estate investing, sales or business. It probably should be mandatory reading in High School.
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