City buses look like this, and they're usually packed three to a seat with a few standing in the aisles. Sometimes a lot standing in the aisles. They usually only cost Q1 (about 12½¢) to ride. The buses are owned by the bus drivers, who are free to decorate them as they please.
Almost all the streets here are one-way, which makes life as a pedestrian vastly easier. Stop signs are in Spanish, unlike in Spain where they're in English, which I always thought was weird.