Add a Handles communication device.
(DOTT Dalek Scene): The doctor talked to him through an audio-link.
When placed in the TARDIS, Handles should get linked to it. Through the communication device (in Doctor's case: earphone type) you can ask Handles to bring your TARDIS somewhere or to teleport you inside it (absolutely canonic, the Doctor did both things).
You should be able to tell him to lock the TARDIS, and to let people in. For example
"Hey handles, let 1WTC inside" = "./tardis-companions add 1WTC".