Functional Elevator Door and Portals  

The elevator is a door (costs 1000 simoleons, located in the "doors"), a technical portal (costs 1 simoleon, found in wall sculptures) + a cabin that is made by hand, at your discretion (optimal cabin size: 2x2 cells + 1x2 field for a technical portal outside the elevator, otherwise the character teleports to the entrance to the elevator)

When the character needs to get to another floor, he enters the room (as I understand it, the portal is activated by the action of entering the room. Autonomous actions with objects located on another floor also activate the portal, but the "run inside due to bad weather" action just drives you into the "cockpit", and if you would like to get to another floor - act like a true programmer - exit and re-enter!