One of the most important questions to answer as you plan your retirement is how much money you need. The answer depends on a lot of factors, from your potential longevity to your lifestyle to how much you’ll be getting from Social Security. However, according to Fidelity, there are four key guidelines that retirement planning should carefully assess. Consider working with a financial advisor as you plan for retirement or update those plans. What Fidelity Found, Based on When a Person Retires Financial ...