I'm not sure if teleporting between condos will ever be an officially supported feature on the official servers. It seems like they want to keep server load to a minimum, so having multiple condos loaded would only increase that load.
However, apparently there are plans for private hosted TU servers, meaning you can host your own Tower Unite server for others to join.
When that becomes available, I do hope they allow server hosts to do more and add/change different 'features', such as setting up and allowing for teleporters, allowing condos to stay perma-loaded even if the host is gone, etc.
Edit: Apparently you can already host your own TU server. Perhaps make a suggestion to allow server hosts to allow use of teleporters? I'm not sure if you even access a teleporter item at all yet (I know they exist... Ball Race... but whether players/server admins can use the or not is another question)