I am using this calculator to calculate the cost of living. https://www.theearthawaits.com/

Very simply, if I take Sao Paulo, Brazil. I selected "Opulent" and 1 person. The budget is about $1,800. So yearly this is $1,800 * 12 = $21,600, lets round to $25,000 to include some extra holidays etc.

So my understanding is that we need to generate $25,000 through 'interest' or 'bond payments' or similar which are around 4-5%. At 4% (being conservative), I would therefore need $25,000/0.04 = $625,000 to invest? Is this correct math? I cross checked it with this: https://www.nerdwallet.com/article/investing/financial-independence-retire-early which says 25 times you spend which is 25 * $25000 = $625,000.

So if I have say $700,000, I can basically retire in Brazil right now? I feel I'm missing something here.

What if I also have a job? I am wondering how I factor in CoastFIRE in here?