Tony Soto is a crime boss in Miami. His position is to the Italian Mafia's capofamiglia in the sense that no crime activity in his turf is executed without his approval. Before criminals can operate in his turf, Tony expects prospective criminals to cut him in on a piece of the action or face consequences.
Tony lords criminal power over unspecified areas in Miami. One of the gangs he oversees is the 24K Crew, which Felix Cole is a member of.
Prior to his incident, Felix made a lot of money for Tony as a car thief. After being humiliated by Corey and Michael Westen, Tony began to see him as weakness. He struck a deal with Johnny that he and his gang, Fiona Glenanne and Sam Axe, would become the new car thieves who get to operate in Miami and remove Felix if they were successful in a job interview test, which is to clean and clone a stolen Maserati so they can sell it. Johnny successfully completed his task, causing Tony to shift to Johnny's side.
After nearly being assassinated (mistakenly) by Felix, Tony decides to put a hit on Felix and the crew. At the same time, Johnny decides to leave Miami, giving Tony time to clean house, but lose control of the car theft game in Miami.
At the end of the Episode, Tony Sato mentions about giving "Big Ed" a call to handle to Felix. Could possibly be the same Big Ed in Season 4 Episode 1.
Some time later, Johnny returns to Miami to ask Tony for information on a car theft ring ( "Brotherly Love"). In exchange, Tony charges Johnny to destroy the chop shop after he has concluded his business. Johnny happily agrees to the favor.
Tony continues to operate in Miami as a crime boss.