I highly recommend taking the Buenos Aires Free Tour. I took both of the tours offered: 11am in the morning (City) and 5pm in the afternoon (Aristocratic). The tours are a great introduction to the Argentine people, history, culture, etc. It was easy to find the starting locations and the guides wear green shirts so you can keep track of them walking around. Speaking of the guides (Maggie and Gaston), they were young, enthusiastic, knowledgable, accommodating, friendly, forthright, and fun. You will have fun. You'll get to walk around several historical, cultural, political areas of BA and meet other tourists who are also interesting. The guides are supported by tips. You can tip whatever you think it was worth the 2.5-3 hours they spend with you. I was more than happy to give them tips at the end. They earned them!
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