Argentina charged us a whooping fee upon entry. It was MUCH higher than other nationalities. They did it right there at entry. Of course, it is good for 10 years. Going to have to keep my soon to expire passport "just in case" we go back.
But then, Argentina is an economic mess.
Tip: if you expect to be able to convert Argentina money back to US dollars (or anything else) upon exit, be sure to keep the receipt you should have gotten when you purchased the Argentine money. No receipt? No exchange.

Doug