You want a shell (You need testingcheats either way)? If you want a shell, put it down first, afterwards you will not be able to move it. Pres the back button if you made a mistake. Behind the "doors" of the shell put in a little room, then put in the "real" doors. (NOTE: It may be more efficient to have a larger compartment connecting the doors, I have not tried this.) You can find call boxes in the electronics tab, they like the communal mailboxes are not required. But begin constructing the lobby and any other public areas, game rooms, gardens, bathrooms, laundry rooms, hallways, etc. Now connected to a closed in public area place a door. Behind this door build the usable apartment. Then place townie apartments, non usable ones. You may furnish these but that is not required. They can be single square spaces behind a door. But these apartments MUST be separated and have at least one square of space behind it for the markers. There are 2 markers you will need, public and hidden. enter in Buydebug to find these under misc. Place the pblic markers anywhere in all public spaces. You only need one in each room, and they will not be visible in live mode. Place hidden markers in townie apartments, non usable apartments, and in random empty spaces you don't want seen. Remember to always place markers first. Now that your whole apartment complex is furnished, shift-click on Townie apartment doors and mark them as NPC doors. Please tell me if this doesn't make sense to you, which it probably won't. I'll just make a tutorial with PICTURES!