According to our Statistical Office of Slovenia...
In 2011, English was spoken by 85% of people aged 25–34, 67% of people aged 35–49 and 45% of people aged 50–64 let.
In Ljubljana, these numbers are even higher.
(for 13% of people, Slovene is a foreign language and most of them do not speak English - manual labourers from south)
Cost of life? Hmm... Not sure how to rate this.
1000 € is an average monthly wage in Slovenia.
Apartment rent from 300-500 € (Ljubljana is more expensive)
Monthly public transportation in Ljubljana 20 €
1L of milk costs 0,8 €
1kg Chicken Breasts in store 8 €
1kg of bread ~2,5€
1 cup of coffee in bars 1,5 €
Big Mac menu 4,6 €
...