I'm not sure if this is an emergency fund question or not but it isn't in my thinking... But how much of a buffer per month do people tend to keep once retired? I "could" live in a box out on the streets and call myself FI but I'd rather not... I live minimally for 1-1.5k/month but should I shoot for that as my FI goal?
Example being I'm single right now but if/when I decide to be otherwise, how do I even plan for that? I have no idea how much a couple spends, is it just double what I spend so $30k/year? Yes I know my partner would have her own income but I'd still like to plan ahead as if there isn't since I can't figure for it now. This is the kind of buffer I'm trying to decide for myself that would be more life changing than an "emergency fund" would provide. Or how about a Californian/New York/Taiwan mustachian would need more than a Kansas/Missouri mustachian but what if I want to move from the midwest to the coast when I am FI, but it wouldn't be possible if I set myself up by midwest FI standards.
So what kind of buffer is reasonable for FI if you wanted to make changes to your lifestyle? I'm not saying I'll suddenly go out and start buying things but small things that kind of last like getting a partner, kid, moving to a new area (yeah these aren't "small changes")? The part of FI planning that scares me is that if I shoot for the bare minimum than that means I can't do anything different out of fear that I'd upset something and not be FI anymore and it would give me a feeling of living "paycheck to paycheck" even if I'm FI. I want to be FI without needing to worry where my next meal is coming from essentially. If I shoot for bare minimum, I can be FI in about 8 years, but I'm shooting for 18 years because I'm looking to replace my entire income. I know 18 years is a long time but I'd be 45 which doesn't seem all that bad? Realistically, it'd be in between the two extremes but I've only "worked" for 3 years which means I'm not burned out yet nor do I hate my job. I could see myself doubling my working life and hitting the 8 year mark and still enjoying the job. But working for 18 years? I don't know.
Just trying map out my future FI plans and polling for how other people do this to put some perspective. Sorry if this has been addressed yet but I didn't see anything and searching for "buffer" didn't come up with anything since most of it is more of a emergency fund type thing and not for changing lifestyles or unplanned cost adjustments.
I'm not sure if I should plan FI with like a 2% safe withdrawal so it gives me a leeway to double my spending and still keep to the 4% rule. So I'd need 600k for my 12k/year current spending but I can double it and still not worry. This also lets the market fall by half and I'd still be within my FI amount or does the 4% rule already account for market crashes and how long do you have to be in the market for this to be accounted for? I know it'd be bad practice to withdraw the entire 4% because someone said that it was "safe" but how low can I drop the % without just having to keep working?
