I've been in self employed business for some decades now and much of the content, for me, was already known, but there were some good points that were helpful even for veterans.

If you're new to business, this can definitely offer up some nuggets of value that will make the investment of both your money in this book and time in reading worth while.

Especially pay attention to the "Freedom Number" concepts. I have used this for a very long time (not under the same name) and it is a guiding principal for helping you to determine some starting points that you have to get to in order to achieve success in your adventures.