If I live in 90% of the US, something like $150k would buy me a very comfortable life. If I was in the major cities, I would say $300k would be enough for me to not worry about finances.
It's not like rural areas are back in a pre-currency feudal era. You still have costs. 150k is very comfortable but you can easily spend it living out in the country, especially if you want to bootstrap a homestead, hobby farm, or just generally make good use of land.