"Liftoff: Elon Musk and the Desperate Early Days That Launched SpaceX" by Eric Berger documents how SpaceX employees poured their blood, sweat, and tears into launching a cost-effective rocket at a time when legacy operators dominated the space market with their costly cost-plus-fee contracts.
This book mostly follows the journey of employees and (thankfully) doesn't resolve to Elon praise too much.
There is a continuation to this book called "Reentry" but I haven't read it yet.