I did not discover this cheat, it is propoty of "abincyprus" on YouTube

First Things First: The Cheat Box! - Open the cheat box (Ctrl, Shift, C). Type TestingCheatsEnabled True, then open it again, and type as writen: buydebug

In the debug menu there is only two "shells". (If you want more shells you need to change premade lots)

Second Step To Sucseed: How It's Done! - when you find the building shell, (the outside of the building) choose to one you want and place it in a vaild location. Then once more, open the cheat box and type: RestrictBuildbuyinBuildin g off

Third And Final: What Makes Up A Building! - Once you have placed your building, you must create a lobby! (It can be a small place to call up residents, or a cool "Richie" lobby with cool lights and toys and stuff. Then add the new objects found in debug menu, called a Hidden Room Maker, and the Public room Maker. Place the HRM (Hidden Room Maker) around to emtey parts of the lobby, and the PRM in the lobby. Add the callbox of your choice, a cool new elevator, go up a few levels and add another elevarot in line with the main one (you can tell where because the squars around it will appear yellow. the add the PRM then the HRM where you don't want your sims to go. Creat a usable room for I'm guesing... residants. If you don't want all those floors, you can put a Level Skip Marker. Open the cheat box a turn RestricbuildBuyinBuilding s on.

Details: If you want to use other shells, turn on the cheats and edit one already made. If you decide you want ot change your building, just turn RestricBuildBuyinbuilding s off and get to work!