I agree with credit card churning being vastly overlooked. (could be a 10K a year deal for most readers here)
I also think that most people, on this site at least, are overly focused on the saving/cost cutting side of the equation when the gold ring is on the income side. MMM would still be a working slob if he was earning 35K per year. Instead his wife and his incomes were well 200K. That is where the real deal is for FIRE. (make more! spend less = FIRE)
But for my money ---- assuming a 10% return with a SWR of 4% when a safer 17% and a 6% SWR is easily doable. That would be a difference of 10+ years working life for most people.
See here -
http://www.milesdividendmd.com/two-faced-investing/ for how to easily use Vanguard funds to achieve the mythical 17% return.
So here are some easy steps to check off -
1. Earn a very good income
2. Invest in tax deferred then taxable accounts at a high percentage of your income (over 65%)
3. Spend very little on crap, experiences and general shit
4. Drive an inexpensive efficient car
5. Buy a home or rent that is less than 2 times your annual income
6. Use a dual momentum strategy to vastly improve your investment results and retire 10 years sooner
7. Cheap cell phone service, cut the cable and other reoccurring stuff.
8. Use Republic Wireless or a very cheap phone provider
9. Churn rewards cards
10. Figure social security and pensions into your equation
11. Enjoy life! Live Better!
Stuff you can safely ignore --- line drying clothes, making your own booze, driving without AC, riding a bike, gardening, freezing in your house, never watching TV, avoiding restaurants.
A big mistake is focusing too much on relatively inconsequential stuff while there is huge low hanging fruit. (see 1-10 above) Yet I do agree that once all the low hanging fruit is picked you can add stuff to infinity. Just be sure you are maximizing income, savings and investment returns as priorities.