If you wanna avoid getting ripped off when buying shit and potentially getting jacked, learn a lil Brazilian Portuguese. Just pick up a book at Barnes & Noble that has phrases and other things you need to know. I plan on going to Brazil this summer and although I'm gonna be with some locals I still wanna know some basic Brazilian Portuguese so I could hold my own. I'll be staying in Rio de Janerio for a while then head to Sao Paulo and probably visit some other places in between. The currency they use is called real and it's value is lower than the dollar so it shouldn't be too bad spending wise.