5. Overinvestment in fixed assets. Consider what you absolutely need before making significant investments. Otherwise, you can find yourself strapped for cash. (I once borrowed money for a brand-new machine that turned out to be a dud. I was better off when I purchased reliable used equipment for much less. But I still had to pay back that initial loan!) If you need office furniture, find a desk at a thrift store and borrow a kitchen chair from home. Voila – instant office. Reward yourself with nice furniture later (much later).