1. Investments
2. Social Security 
3. Pension  
4. Profit-sharing 
5. Income from work after “retirement” 
6. Other areas like reverse mortgages 

• Monthly expenses like rent, mortgage payments, food, clothing, insurance etc.
• Special expenses like vacations and one time purchases, etc.
• The inflation rate
• Taxes owed
• Give special consideration to Financial planning
• Asset protection
• Reducing expenditure/modifying lifestyle
• Living Longer

Current mortality tables show that an average healthy American male at age 65 today can expect to reach approximately age 85 - but that same individual also has a 50% chance of living beyond age 85 and 25% chance of living beyond age 92. As a result, people who plan to cover their economic needs to their "life expectancy" - in this case, age 85 - still face a 50% chance of failure. The Wharton study explains that only lifetime income annuities can mitigate the financial risk of living too long by relieving consumers of the need to set aside the far greater sums they would otherwise need to allocate to other asset classes to ensure they would not outlive their retirement savings.

From Retirement Weekly
Taking money out once you are retired. Some retirees take too much money out during the first few years of retirement and don't have enough left for their later years. Some retirees are too frugal and don't have the opportunity to enjoy their retirement. They skip vacations, don't eat out and scrimp to the point that most of their savings go to their heirs. Some retirees don't take the minimum distribution of retirement funds mandated by the IRS (after you reach 70 ½) and have to pay stiff penalties.

Some retirees move all of their retirement assets into money market funds and lose the growth that stock and equity funds produce. How can you best avoid or at least best protected yourself from these mistakes?

My suggestion is find a good financial advisor and let him/her guide you. If mistakes are made you at least know that you have made every attempt to avoid them.

If you provide a financial advisor with the information he/she needs as far as what your expenses are and what you hope to spend each year during your retirement, he/she should be able to come up with a plan that will maximize your chances of meeting your needs. If your retirement funds are substantial you would probably also be wise to work with an estate planner in conjunction with your account and attorney.

Obviously as you get closer to retirement your investment strategies should change. By the same case once you are retired, where you have your funds and how you generate income and where you get money for every day expenses should change substantially. Unfortunately we regularly hear how unscrupulous con-men (and women) have separated seniors from their hard earned savings. We have also heard that if it sounds too good to be true it usually is a bad investment, but far too few seniors take this advice to heart. Early withdrawal generally should be a last resort.

The federal tax penalty for taking money out of a 401(k) or IRA before age 59 ½ is 10% of the amount of the distribution. That penalty goes on top of any tax owed on the amount withdrawn. State taxes and penalties may also apply. For example if you were to take $1000 from your retirement account in additional to your federal tax you would have a federal penalty of $100 plus possible state taxes and penalties. Be aware there are certain exceptions that would allow you to avoid the penalty but not the tax. It is important to talk with a CPA or accounting professional if you plan to make an early withdrawal.