Just to know if I were to create an apartment complex, after I have assigned every family to their apartment then choose to play with another famlly which does not live in this complex, will the apartment mod still function, as every families will still choose their designated rooms as home?
Apprecaite your help simmers

Are you referring to the Apartment Mod by Ani? If so, then yes, the Sims you assign to each apartment will stay assigned to them even when you switch to another household. However, you will also need to assign the EA door lock function as well to each Sim in each apartment and if you are using NRaas Story Progression as well, disable the Allow Move option for the Sims you are leaving as unselectable.