Cost of living in Mar del Plata (Argentina) is 26% cheaper than in Zapopan (Mexico)
This comparison is lacking data. It provides a decent comparison, but it is not yet reliable. It is based on 477 prices entered by 34 different people.
For example, to keep the same standard of living that would require Mex$ 44,000 in Zapopan you would need to make just about Mex$ 32,525 (ARS $35,121) in Mar del Plata.