Be careful going to Uruguay if you are renting a car there. My wife's cousin just went and she was surprised she had a hefty fine for previous speeding tickets in her rental car. There are cameras all over and fines have been accumulating.
My neighbor had the same thing happen to her. She just got back but she had her own car that she takes on Buquebus. I will have to ask her if she was given the chance to just turn around. She had a few hundred dollars in speeding tickets.