Since they have contacted you again and are threatening further action, I would immediately lodge a complaint with the ACCC for "unfair contract terms". The alleged "liquidated damages" are nothing more than a penalty (fine) and in no way reflect actual losses or costs.
Furthermore, if there is nowhere else to park within reasonable proximity of the shopping centre, then you have no say in "By accepting the parking terms, you agreed to pay liquidated damages if you breached the parking terms" which is also an unfair term in the circumstances.
Also, where are the amounts of these "liquidated damages" defined and for what "breaches" do they apply? Where is all this information displayed?
If it's only displayed at the entrance to the carpark, then it is not reasonable to expect customers to hold everyone up while they stop to read all these alleged "terms". Doing so, would actually lose the company business.
Given that is the case, you can argue that in these circumstances, there is no proper opportunity being given to customers to read and understand the terms and conditions before entering into a contract and therefore, it is not reasonable to accept that entry alone implies consent to those terms and conditions. As such, the terms should not be enforceable and should be void to the extent of their application.
All parking companies know this and use this knowledge to their advantage because they know that no-one is going to stop and actually read the plethora of terms displayed at the entrance. Maybe if everyone started doing exactly that, then these a**eholes would finally get the message.
The company is clearly profiteering. Ignore everything they send unless it's a hearing notice, and lodge a complaint with the ACCC. If enough people take the time to actually complain about this kind of crap, then the ACCC will do something about it.
