This was my game changer book. I realized I was actually shorting the customer of a great experience by not asking if they'd like more. Definitely a great read.
Go for No! Yes is the Destination by Fenton
Another fantastic read that Preps your mind to think of the end game first.
7 Habits of Highly Effective People
Honestly, this can be applied to all areas of your life. It's a book I plan to reread again and again.