After taking the ferry from a rainy Ilha Grande to Angra dos Reis we were to take the bus to Paraty.
During our research before we found out the following: The nice, comfortable bus run by Costa Verde that stops in Angra and continues to Paraty does not sell tickets for this part of the journey. Instead we are to take the Colitur bus which leaves more or less 2 times an hour all day but is not very comfortable. It is actually a regular city bus that is used for a longer trip.
Our hostel manager let us know that this is the only option, and that it leaves from the last bus hut on the docks when walking away from where the ferry drops you off. At the price of €2.50 it might not be worth to complain about the comfort. The bus works as any other city bus, you get on, pay, pass the turnstile and sit down.
This was our view for the 1 hour and 50 minutes that the journey took. Every speed bump meant that the seat first left you underneath and then came back and hit you real hard. But it was cheap.