[QUOTE=Mendez;456625]Isn't it possible to get foreign money from ATM's?[/QUOTE]I don't think you can get USD out of an Argie ATM.
Getting ARS before traveling is a pain in my ass. I'll pay the ATM fee at the airport for my first fistful of pesos for walking around money.
Grab one of these travel wallet things.
[URL]https://i.pinimg.com/originals/22/d8/ac/22d8acd845671c5fe9d790f0c896d99b.jpg[/URL]
Stick a grand or two in it (before you leave the US) and tuck it in your pants (don't put your passport in it, its a PIA). This thing doesn't come out until you're in your hotel room. Take what you want to exchange and put the rest in the safe along with a credit card and your driver's license (won't do you any good unless trying to establish your identity at the US embassy) and a photocopy of your passport. That way, if you end up having 'problems' you'll still have the resources necessary to get home.
The ATM fees, over the course of a week of mongering, will add up to at least an hour or two with a lovely lass.