Gone are the days when people could retire at age 62 and live off the income from their bond portfolios.

Roger Roemmich, a CPA, long-time wealth manager and author of "Don't Eat Dog Food When You're Old," said that people heading into retirement are focusing on the wrong variables. They should pay attention to investment hazards, asset allocation and how much money they have set aside for retirement, he said, but the one missing component in their planning is cash flow.

"In my view, if they would focus on cash flow and continuing cash flow versus expenses as opposed to how high they have to pile their assets, they wouldn't make mistakes about retiring at the wrong point in life," Roemmich said. "Too many people in my generation, I would say 80 percent, are retired at age 66. That's a mistake. A lot of people will experience problems cash flow-wise."