In Jeff's first year in Greendale he struggled with his finances and was no longer able to afford the luxuries he had when he was a high priced attorney. He was eventually forced to give up his expensive condo and settle for a much smaller apartment. The apartment made a brief in the Season Two premiere "Anthropology 101" and was later fully seen in "Early 21st Century Romanticism".
In his first year at Greendale, Jeff was still getting used to the fact that he could not afford to live the expensive lifestyle he enjoyed as as a lawyer. Although Jeff kept his cell phone and his car he was unable to keep his beloved condo and was evicted. He ended up living in his car but despite his circumstances, he still believed that he would be able to move back into his condo. When his car was towed and having no place to turn he moved in with Abed in his dorm room. Abed realized his place was having a negative affect on Jeff and asked Britta to convince Jeff to snap him out of his funk. Britta broke into his condo and stole Jeff's hand crafted Italian faucets to inspire him to move on and install them somewhere else ("Home Economics"). Jeff took her advice and eventually found an apartment he could afford and moved in. He would later note that his new place as having a Spanish family down the hall that hates him ("English as a Second Language").
Jeff's apartment is seen for the first time in a brief shot of him doing hanging sit-ups in his bedroom ("Anthropology 101"). Later in the semester on Valentines Day, Ian Duncan invited himself over to Jeff's place to watch a Manchester United Football game. Chang learned about this and joined them with an ulterior motive. He turned the get together into a large part and invited various students from Greendale, sans the study group, including Star-Burns, Leonard, and Magnitude. Using the party as a smokescreen, Chang attempted to sneak in his belongings and secretly move in with Jeff. He had been kicked out of his home by his wife due to his brief affair with Shirley. Upon learning of his plans, Jeff kicked him out and ended the party. However, a conversation with Duncan about accepting his time at Greendale made Jeff have a change of heart. When Jeff discovered Chang was still at his apartment complex inside the trash chute, he allowed him to stay at his place for awhile ("Early 21st Century Romanticism").
Sometime later, Shirley hoped Jeff could convince his then roommate to waive any legal rights for her unborn child which she learned earlier could possibly be his. In an attempt to get him to move out, Jeff instead made Chang think that Shirley would allow him to be a part of the child's life if he got his act together. In order to prove he was father material, Chang picked up from school kids he thought were Shirley's children and brought them to Jeff's apartment. When he learned they were not Shirley's kids he kept that information from Jeff who got angry at Chang and berated him for his reckless actions. When Jeff left the apartment with the boys to return them to their parents, Chang sent the police after him and got him arrested for kidnapping. With the help of Shirley and Andre, Jeff managed to have those charges although he ended up spending a night in jail ("Custody Law and Eastern European Diplomacy").
Jeff's apartment is not seen throughout his third year at Greendale. It's assumed Jeff kicked out Chang sometime before the summer break as he ended up living in the school vents by the time the new school year started.
In December of his senior year, Jeff's apartment is featured prominently after he invites the study group and Chang/Kevin to a Christmas party. Annie reveals she invited their History professor Noel Cornwallis in the hopes of getting him to change the grade of the group's history paper. The party degenerates into another kidnapping scenario after a misunderstanding from a supposedly amnesiac Chang holds Cornwallis against his will by tying him to a chair. Jeff attempts to take advantage of the situation by extorting a passing grade for their paper while they have the advantage. In response Cornwallis begins to play mind games with the study group and by tries to get them to turn on each other. The tension filled situation is resolved when it's revealed that Cornwallis had orchestrated the entire thing simply to amuse himself. Jeff then negotiates a passing grade from the professor for all the mental anguish he inflicted on them ("Intro to Knots").
In Season Two it is established that Jeff's apartment is on the right side of his apartment complex hallway across from a trash chute. However in Season Four his apartment is seen at the end of the hallway and Dean Pelton's apartment seems to be where his originally was located. Additionally, Jeff's apartment is much larger than previously shown and seems to be a redress of the Winger residence.