I'd say it's mostly a matter of energy and time you wish to put into becoming a successful entrepreneur. My experience tells me that first two-three years is a grind, then you can loosen that regime a bit, depending on what you want to achieve. If you're ok with making more (like x1.5 - 2.0 times more) than when employed you can relax and settle on 8-10h a day, if not - real benefits come later, but I think you'll need to hire somebody anyways.