Erica gave a very interesting and educational tour of downtown Sao Paulo and rather than trying to find my way through the crowds from one place to another, it was a relief to not worry about where I was going or to look at maps (the Brazilians don't use them, they ask someone where a place is). I could just drink in the feel of the city and learn about the sites where we stopped and look less like a tourist. You will get a much more efficient use of your time with a guide than going on your own. But...wear your walking shoes - she loves to walk and we spent close to 4 hours exploring downtown. Great value - good experience. Vale a pena (it's worth it).