well i'm 37 and can't wait for retirement. . . what type of money do you guys who are retired spend a month? I try to add up what i would need (with everything paid off) i figured that 5k a month would go a long way, my dad tells me i don't have a clue. he tells me that to retire i would need to have an income of 8-10k a month.
What I have done, usually about once or twice per year, is make a budget listing of all the items that must be paid. Utilities, cable?, insurances, maintenance, food, clothes, dog care etc. Autos will eventually have to be replaced, so I put in amount that represents buying an auto. Items like that are easy. Make a product lifetime estimate in years, multiple years by 12 to get months. Divide the estimated replacement cost by the months. Add a line to your budget in that amount.
Of course, make the list as complete as you can.
Next I convert all non-monthly costs to average monthly amounts, so everything is on a monthly basis.
Fot things I don't know or know will change, I try to make realistic estimates. Look up some on-line quotes or whatever. Health care/insurance is probably my biggest unknown.
The total at the bottom is my monthly 'survival' budget. Any extras for a trip or whatever would be additional.
I do the same thing for savings and investments. Take current readings and interest/return rates and calculate how much income I would have on an average monthly basis.
Then I compare the results of the budget and income estimates.

Dave.