How to Convert Residential Lots to Apartment Lots in "the Sims 2"by Contributing WriterUpdated September 22, 2017
The creation of the Sims 2 Apartment Life left many players ready and eager to build condos and apartments. Finally players could have multiple families under one roof but still have them live separate lives. But if you're dreaming of creating your own apartment instead of the pre-made ones that come with the game, you've got to take action.
Make sure you've built your apartment correctly in a residential lot first. This includes having the apartment door facing the correct way and making sure there are no other exit doors in the apartment--even balconies should be closed in. The place should also have the basics such as hardware that would normally be found in an unfurnished apartment and absolutely no Sims should be living on the lot. Move them all out before the conversion.
Access the cheat window by pressing control, shift and the letter C simultaneously. The box will show up in the upper-left corner of the screen.
Type "changeLotZoning apartmentbase" and press enter. Look for an error code to pop up on the screen. If you receive an error code, this means you have another entrance or exit to the apartment or you've made an error with the apartment door. Look at each apartment carefully to make sure neither of these mistakes have been made.
If you type the cheat code and the screen stays as-is without a pop-up, you've correctly changed the lot zoning. Save the game and then exit to the neighborhood. From the neighborhood view, you should see the apartment icon--a square, rotating symbol, above the building. When Sims are moved into the apartment, the residential mailbox should then become an apartment, multi-stacked mailbox, showing the conversion was complete.
Check out the EA Games apartment building tutorial in the "Additional Resources" section to make sure you're building correctly and apartments meet all building needs. Also make sure garage openings are beside the doors to the apartment and are accessible to the Sims from inside. Otherwise, they will not be able to claim the space as their own or purchase a car.
Do not convert a lot while a Sim is on it no matter what because the game will crash. Even to make subtle changes in building, you will either need to use another building or moving cheat, but it's suggested to move the Sims out and move them back in once you've made your changes to prevent game damages. Use cheat codes at your own risk.