Ok, now I understand what you guys have been trying to say. And I think I know what's happening and why the dropdown isn't giving you the choice to create new units when the only choices on the dropdown are shared and a single apartment. That's all you have access to in live mode so what I think you guys are doing is trying to make new apartments in an owned building and going to build mode directly from live mode. So, you'll need to backtrack a bit and basically start over to get the rooms assigned to the apartments. While some editing can be done going to build from live, you don't have access to the entire building going that route. It has to be done when the building is unowned, and you go to build from the map.
1st - make sure all the spaces are assigned to shared. If it won't let you do that, it'll probably be ok.
2nd- change the venue type back to residential.
3rd - If you are trying to convert a played lot that has collectibles and sim's career rewards and personal things like birth certificates, etc., collect those and put them in either a sim's inventory or the household inventory so they will stay with the owning sims when you move out.
4th - Move the sims out and sell the lot leaving the furnishings.
5th - Go to the map and enter the lot in build mode.
6th - Change the venue type to residential rental.
7th - Assign all rooms for apartment 1. After you finish assigning rooms to apartment 1, select a room that's for the next apartment, then use the create option on the dropdown and it will add apartment 2. Then proceed to assign rooms to apartment 2 and move on to the next until you've set up all the apartments. When you are done assigning all the rooms to apartments, exit to the map. If you want to save the lot to your library, do it before you exit the lot. Btw, rooms assigned to an apartment don't need to be contiguous. I built a building with 6 apartments and was able to give each apartment a section of the basement to store stuff. It just has to be accessible without going through space assigned to another apartment.
From there, you can have a sim buy the residential rental via the phone or a computer. You immediately get sent to the lot you bought in build mode. If that sim owned the lot they were living on before, you'll have to return to it and move out, selling the lot and move to the apartment in the residential rental you want the landlord in. OR you can move the sim to the apartment first and then buy the residential rental. Their apartment becomes the landlord's apartment either way. And the landlord can live in any apartment. It doesn't have to be apartment 1.
The key thing here is that to assign rooms to apartments is the lot must be unowned and it has to be done going to build from the map. It won't work going to build from live mode.
One caveat. If you downloaded a lot from the gallery and ran into the same situation where the only choices you get on the dropdown are shared and apartment 1, you can't fix it. Lots that do that were uploaded with a sim on it at the time of the upload will not let you create new apartments and give you an error that a sim is on the lot. The only one that can fix the lot in that case is the original creator. There may be other reasons it happens too of which I'm not aware.
Hope this helps.
How do you do point 7, assigning the rooms to unit 1?
To assign rooms to an apartment, first go to build mode from the lot. The lot must be unowned and have no sims on it and be assigned the residential rental venue type. Then you click on a room and get the room outline up. There should be a dropdown for that room that lets you assign that room to shared or an apartment. Once you've done that for every room, you can exit the lot to the map. then go to the household you want to be the landlord and have a sim buy the lot. If you want to just use an NPC landlord, just move a tenant in using Manage Households.
Hope this helps.
