Avoid the top 8 retirement-planning screwups
Avoid the top 8 retirement-planning screwups

The potential pitfalls threatening a successful retirement are many, and the biggest errors fall into both psychological and financial categories, according to financial advisors. CNBC spoke with eight advisors, who between them came up with the eight most common mistakes made in retirement.

"The greatest concern we have with our clients is the psychological part," said Michael Randolph, senior advisor and certified financial planner with Willow Creek Wealth Management. "They'll say: 'What do I do? Paint the fences? Then what?'"

Advisors get many retired clients who are "lost" and not focused on their finances or their future, he added, because after having been very successful throughout their career, they now feel they no longer have a sense of control.

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"They feel cast adrift, [and] it's troubling, [so] it's very important to think it through before you retire so you know what to plan for," Randolph said. "If you don't have a great deal of clarity for what you want by retirement, then when will you have it?"

Many people don't understand how to allocate resources over an unknown period of time, according to Kathleen Roth, a certified financial planner and partner with Waterstone Partners.

"The biggest thing is learning to accept that there might be a change in lifestyle and to live peacefully with that," she added. "But when you talk about budgets, people shut down."

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As people feel they can no longer do what they want and regret perceived past carelessness, Roth said "it brings about a sense of denial and pain."

According to Roth, retirees need to learn new thinking skills, including:

-Getting in touch with personal values (i.e, realizing "it's us against the marketing machine").
-Making tough financial choices (i.e., eliminating the expenses-designer clothes, latte coffees, takeout meals-that put them at financial risk).
-Being mindful of cash flow.

Another area of erroneous thinking is going it alone. "Many baby boomers have a do-it-yourself mentality; they're used to going online to do their own research," said Michael Salley, wealth manager and president and CEO of Salley Wealth Advisors Group. "They think this holds [true] for financial planning, as well."

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Without professional assistance, retirees typically will underestimate and overlook their financial needs.