Would a co-founder in that case be beneficial? Assuming you both take the risk, it's less hard on you if it fails. Obviously pros and cons with this.
Honestly the safest option seems to be relocating to a third-world country where the labor and the cost of living is cheap, so that said money can be stretched out over a few years. Or waiting til that pile of money gets a bit larger and living off ramen for a while
There is a large part of Europe (and I'm sure the US) where the standard of living is decent and you can easily get by on <15k€/year.
Right now I have my eye on either Latin America, rural Northern California, or Nevada. Humboldt area is very cheap right now, I am seeing 2br houses renting for $1000 and studio apartments for 3/4 that in Eureka (which isn't all that bad; I just visited)