Cost of living in Banja Luka (Bosnia and Herzegovina) is 38% cheaper than in Zaragoza (Spain)
This comparison has some inconsistent or sparse data. It already provides a reliable comparison but it is not bullet-proof. It is based on 381 prices entered by 30 different people.
For example, to keep the same standard of living that would require €2,200 in Zaragoza you would need to make just about €1,358 (2,660KM) in Banja Luka.