Ten years ago, when I worked at a large investment company, management hired 25-year ex-CIA and FBI veterans to teach me how to tell when a CEO is lying to us. This helped me tremendously to avoid investing in companies that had misleading or unethical CEOs.

One of the biggest mistakes people make in sales is that they oversell. If you do this, your buyer will think that there is something wrong with your product or that you are desperate to make the sale; caveat emptor. Once you think that the buyer wants the product then stop talking.