Emigrating halfway across the world is not cheap in the first place.
Greece is also not cheap for where it stands on the economic level compared to the average income, especially back in 2018 when Dylan did it, and especially for property even outside of urban areas. Euboea is not super remote either, it's about an hour or two's drive from Athens depending where you go.
So sure, the farm might not make money, but I would wager he had a good amount saved up between him and his family to make the transition possible.
This blogpost might generate more profits, but I doubt they are even close to being profitable and have other income/savings.