Add-on content in The Sims 4 has immeasurably improved the game with free and paid additions, giving quality-of-life and themed additions. Additional content is a normal part of how The Sims series has worked since the very first game, but some features of The Sims that remain as add-on content are so crucial to the series that they should be shipped with Project Rene's base game. One of these features is the ability to create apartments, which was introduced with The Sims 4: City Living.