Cost of living in Aveiro (Portugal) is 14% 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 250 prices entered by 19 different people.
For example, to keep the same standard of living that would require €2,800 in Zaragoza you would need to make just about €2,421 in Aveiro.