As your car park is classified as a private lot you may tow unauthorised vehicles if you wish to take those steps. Unfortunately building management has no authorisation for car parks and cannot assist. You can install a car park bollard to avoid unauthorised vehicles but please be aware you will need to seek Body Corporates approval. If you are found to be parking on “common property” (any space within the car park that is not a private spot) you will be fined by the Stonnington Council. Please find alternative parking if you are stuck without a car park.