I don't know if there are places you should avoid, just be careful! For example, if you're interested in Tango and all that stuff you should go to San Telmo, it's a very nice place, but try to stay on crowded streets. There are lots of tourists there, so go to the places most of them go, stick with your group if you take a guided tour... and have fun! Don't be too worried... hope you have a great time
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saint, we'll meet one day, don't worry
rukas, let me know if you come here, if you need to know something, just ask me