I only spent a brief weekend in Buenos Aires. So I only have a few notes. The people are warm and friendly. Bank or credit cards are widely accepted in the country - make sure to have no foreign transaction fees, etc. - but cash is hard to come by. It is pretty expensive at many of the ATM’s. There’s several black markets for cash exchange on some busy avenues and in commercial areas. People will generally call out to you. Exchange at your own risk.