Another option is to retire early in a country with a much lower cost of living. You don't need to cut your costs to the bone for 20 years if you go to a place

Another option is to retire early in a country with a much lower cost of living. You don't need to cut your costs to the bone for 20 years if you go to a place with a cost of living that costs one-third (or more) of what it costs where you currently live.