Do you have a business that is or has been profitable? If you don’t mind giving away the secret, put together a book and teach others how to start the same business. This is best when your business idea, if started in other cities throughout the world, would not affect your business. There would always be a chance of someone local getting your book, but this type of book usually sells pretty well, so it may be worth the risk.
Avoid writing and selling a book on how to make money just for the sake of selling the book – with no real proof that your idea really works. In short, avoid writing and selling “money making scam” books. You might sell some books in the short run, but in the long run if your plan really doesn’t work you are doing a disservice to the public and it will ultimately fail. Sell a high quality business “how to” book and you will do and feel much better.