For Malakito:
Your estimated expenses are much too high. Dory36 has an excellent write up about retirement needs somewhere on these boards. I will be looking for it and I will link you to it when I finally locate it.
malakito: I am not sure if they are too high or not. I posted a poll way back on TMF about retirement expenses versus pre-retirement expenses and the consensus then seemed to be that you needed 100% of pre-retirement expenses in retirement. This poll was conducted among early retirees, and there were a number of replies, so I think that is the best I can do for now. I agree that I will have to re-shoot the number using a more detailed approach at some point in the future when I get closer to FIRE.
As an aside to Cutthroat: I used to use annual numbers, but I now use monthly numbers for two reasons: It's easier from a spreadsheet point of view, and it will hopefully at some point reinforce to my wife that our expenses can swing my retirement date in either direction by several years (yearly data doesn't have as quick of a feedback loop). When I do a more detailed look at things I will certainly look at data for a full year if not longer.
First: your house should be paid off (or very close to being paid off). You will have no mortgage expenses.
malakito: Yes. I don't have an actual plan to pay off my house yet, but what I do in my spreadsheet is subtract my projected outstanding mortgage balance (easy to do with a fixed rate mortgage) from my projected investment assets before calculating my Spending/Assets ratio. Currently interest expense on my mortgage is my largest or second largest expense (taxes is the other top one). I don't count the principal part of my mortgage payment as an Expense; I treat it as an increase in net worth because it increases my home equity. I don't include home equity in my assets for the purposes of the 4% rule, though. I consider my home equity to be a fall-back asset for a reverse mortgage or HELOC if things turn ugly.
Next: you will not pay social security taxes.
malakito: Yes. Also, my income taxes will drop by quite a bit, primarily because I won't have to pay taxes on the money that I am earning and saving during my earning years. Overall I assume, and this is a very rough and crude assumption, that my overall tax burden will drop by an amount equal to the increase in my health care insurance premiums.
Next: you will not be contributing to your retirement account.
malakito: Yes. I don't consider this to be Spending, because in Quicken it becomes a transfer from my paycheck to my 401(k) for example. So this is considered an increase in my Assets.
Next: you should have very little coverage in the way of term life insurance.
malakito: Yes. However, the amount I spend on term life insurance now is, relatively speaking, a rounding error compared with other spending. I already project our life insurance needs and have already started reducing it as our assets grow. I certainly expect to have no need for insurance by the time I reach FIRE (by definition) and possibly sooner.
But: you may or may not get health insurance among your retirement benefits. This is critically important. Even now! You need coverage before you get any kind of illness. Otherwise, you might not get coverage. This varies from state to state. The time between beginning retirement and getting Medicare is critically important.
malakito: Yup. I will be 51 in September 2020, so Medicare coverage would presumably be 14-16 years away at that point (I know my "full SS age" is 67 since I was born in 1969; I don't know if Medicare has adopted the older age thing too.) Currently I am covered through my employer and will plan to get catastrophic coverage at retirement, paid for by the reduction in my tax burden, as noted above.