"Remember that when you're giving away equity, you're getting married to your investors. Make sure that your value and ideas are in synch. And keep in mind that if your company ever wants to borrow money in the future, it's likely that any investor who owns 20 percent or more of the company will have to guarantee the loan personally. Will your investor be willing to do that? And if your investor is promising expertise and help the way the sharks do, make sure they spell out precisely what they mean before you sign."