Three of my favorites are How Much Should I Charge Don't remember the author, but she reinforces the point that most small businesses are undercharging for their product/service and shows how to solve the problem. The E-Myth Revisited kinda starts where the above one ends in that it points out the tragic flaw in many entrepreneurs: they want to practice their "craft" to the detriment of the actual business. Growing A Business my copy of this disappeared over 10 years ago, but I still consider it one of the most important business books I've ever read. And pick up one of the many editions of The Portable MBA at a used bookstore. Good, basic foundations in Finance, Accounting, Marketing and HR.
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