I'm building a startup and because I have no experience other than a great idea, I enlisted the help of a mentor. Since then, I've been working with him and paying him by the hour. Now that I'm getting ready to hire a team, the mentor offered to come on board as the CEO and wants a certain percent of the company. Until I raise enough money, he said he'd work on a part-time basis at a reduced rate. What ownership percentage is normal to offer? I really need his help, but should I find someone else to be CEO?