A hefty salary doesn't necessarily mean that you can save a ton of money at the end of the month, or that you can afford big expenditure on leisure activities and luxury items. Cost of living has a direct impact on all of the above. Starting with the least expensive, we present to you America's ten most expensive metropolitan areas, where a six-figure annual salary for a family of three isn't enough for a comfortable lifestyle. After paying their taxes, debts, housing, and transportation, a family earning $100,000 a year is still struggling to get by in certain US cities.