I speak Portuguese or should I say I communicate in Portuguese, many of the words I use are constructions that don't exist in any language but there is no problem with mutual understanding.

I visit Brasil 3-4 times /year but have never been to Brasilia - I don't like cities that are not easily navigated by public transport and that is the impression I get about Brasilia. I have no problems with Curitiba, Rio, Salvador, Sao Paulo, Fortaleza. I sort of felt that with 3 hours between flights in Brasilia, I could do a quick run around the city and get some idea about whether I liked the feel of the city and maybe devote a few days to a trip there in the future.

The R100 for a taxi for a couple of hours I base on the fact that the Taxi tariff in Rio for waiting time is around R25/hr and apart from the trip to and from the airport I don't imagine that there would be more than about 20km of driving between the main buildings of interest in the city - does that seem reasonable?