FIRE in 12 yrs... starting with a portfolio of $0, 100K a year. Strategy?
Is that 100k income, or 100k savings/yr you can manage? If savings, 100k x 12 years = 1.2MM, you'd just need a CAGR of just under 4% (real, assuming all dollars are kept in present value).
If it's income of 100k, to hit 1.5MM in 12 years, you'd need to save ~69% of it, or 70k or so, and live on 30 (including taxes, so hopefully that 100k is net, or you can get your taxes really low).
Of course, that assumes you're only spending 30k for the next 12 years, but your ER spending is 45k (3% of 1.5MM), which is a disconnect. Maybe you want to spend more (traveling or whatever) in ER, but a 50% spending boost is a big bump. Or you'll have to have big cuts for the next 12 years.
I would submit that you may be doing it a bit backwards, picking a date (12 years from now) first. Instead set your spending level and look at your income, and calculate the FIRE time from there:
http://networthify.com/calculator/earlyretirementThen work on moving it sooner, if it's more than the 12 years you want, by playing with decreasing spending/increasing income.
Good luck!