Apartment

An apartment is a lot where Sims can live in The Sims 2: Apartment Life. It is similar to a dormitory, however unlike a dormitory, anyone of any age can live in it. A household can live in an apartment by selecting a room's door, and selecting "buy apartment(-§). The player can edit out the flooring and appliances but can't remove objects that already exist in the room (e.g. sliding dresser, fireplace) without using cheats. The Sim also needs to pay the rent whenever it's scheduled.

Sims can complain to their neighbors if they make too much noise, using the "Knock on Wall" interaction or knock on their door and blurt out the complaint.

Sims could also decrease their rent by having a high relationship with the Landlord or Landlady or by having a Roommate that will help pay the rent. However, a Sim's rent will increase when they make too much noise or neighbors complain about them.

Bug
There are some troubles between The Sims 2: Apartment Life other expansion packs when living in an apartment:
 * With The Sims 2: Nightlife, after having a dream date or rockin' outing, sometimes other sims will sneak and put a present in front of apartment, like pinball or DJ booth. However, the item cannot be sold or even be moved. It's very annoying because when the sim has had many dream dates and many presents in front of the apartment, it will block the way!
 * The Sims 2: FreeTime, when a Gypsy Matchmaker came to give a magic lamp, she will also put the magic lamp outside the apartment. And again, it cannot be moved too! But don't worry. When you play other family in the same apartment, the items won't be visible and road will be clear. However, when you play again the same family, the items will still block the door!

These bugs have been fixed with the Patch. "Dream Date" reward objects can now be picked up in Buy mode on Apartment lots.

The Sims 3: Late Night
While interviews and trailers may hint at the existence of apartments in The Sims 3: Late Night is was revealed by Grant Rodiek in a Q&amp;A session on Twitter that the high-rise apartment buildings shown were merely 'shells' similar to Pyramids in World Adventures. 'Apartments' in Late Night will function just like a normal redidential lot in The Sims 3.

This fact was also confirmed by SimGuru Nita who says...

We do not have apartments in the same way Apartment Life had an apartment. Your Sims are able to live in high rise like structures, some luxurious, some a bit more middle class. In them, your Sims are limited in how and where they can build (like an apartment). There’s a lobby downstairs with a callbox and elevator. You may see other Sims move in and out, but your active Sims are the ONLY ones who really live there.

We focused on the coolest part of living in an apartment – the view, the limited space, the elevator entrance, but do not have complex gameplay built around communal living

Building Apartments (in The Sims 2: Apartment Life)
A user can use pre-designed apartment buildings, or can design their own buildings with the use of the 'changelotzoning apartmentbase' cheat. A user could, in theory, build many types of rental dwellings, from bachelor-sized apartments, to multiple houses sitting on one subdivided lot, to single houses that contain multiple households, to even a single rental home sitting on a lot; the builder need only meet a certain number of requirements.

First, all units (individual apartments, for instance) must be completely separate from one another. There can be no doors that lead directly from one unit to another one. Units must have only one connection to "public space" (any area intended to be outside the units i.e. hallways), and such connection must be the Unique Separator door. The Unique Separator is the door in the build menu that comes with a doormat - the doormat and door are changeable, but the mat must face outside the unit for the apartment to be considered whole. Apartments can span multiple floors, but an apartment on a foundation may not have a connection to the ground (if, for example, the apartment were a house with a fenced-in backyard and a deck).

Once the unit(s) are completed, the 'changelotzoning apartmentbase' cheat is used to convert the building from single-family residence to apartment. If the apartment is not built correctly, a pop-up will appear telling the player this, and will tell them to use the 'changelotzoning residential' cheat to go back and identify the mistake(s). If the apartment is built correctly, the lot will be changed to an apartment, and will appear as an apartment building when seen from the neighborhood. Make sure all architectural and structural changes are made before the conversion to an apartment. Because of the Build Mode restrictions in apartments, making major changes to the structure are impossible after the lot has been rezoned.

There is no maximum number of units in an apartment complex, but the user may only place 4 families in the building, so any remaining units will be available for Townies to move into. Users with less powerful computers should avoid building apartments that are too large, since large buildings with many units and many families will drain system resources.