If possible, set aside six months' worth of living expenses to cover your housing costs and other expenses while you work to launch your business, said Peter Miller, a certified financial planner and president of Zoe Wealth Management.
Miller launched his firm five years ago after deciding to make a career change in his early 40s. At the time, he and his wife set aside $25,000 in savings to help cover their costs as he ramped up his practice. They agreed that he would rethink his plans—i.e., get a job—if they came too close to spending down that money, Miller said.
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"If you are going to step out of your comfort zone and make a reasonable decision to invest in your growth as a person, then you don't want to put your family in financial peril," Miller said. "So put some money aside [first]."
Ask yourself whether you really have a passion for your business idea. After all, you don't want to leave a job you dislike to find yourself running a business for which you have no real passion. If you aren't sure what makes you tick, you can work with a paid coach or take a career-assessment course, among other steps, to try to figure that out.