NASTY PCNs : PRIVATE  PARKING COMPANIES' MONSTROUS LIES 

Firstly these fraudsters dress PCNs up to look like fines because most people see them as compulsory and unavoidable payments , the consequence of having committed a crime.  The truth is these parking charges are nothing more than a claim for liquidated damages as an agreed consequence of a breach of contract ,  which of course is a civil law matter.
The rationale should always be that the sum is a genuine pre-estimate of loss , which in the case of parking violations is never the case. Losses for overstaying can be no more than the difference in tariff charges. Losses for non-payment essentially amount to the tariff charge which should have been paid. Losses for entering incorrect registration number details are zero. In other words hefty parking charges should be deemed under contract law as unenforceable penalties . Administration fees for chasing up drivers' address details might be a genuine loss which these companies are able to claim back , but these can be no more than £10-15. 
But heaven forbid should a motorist ask for a breakdown of the liqidated damages sum. Repeated requests will be met with repeated silence. Why ? The answer is simple : companies cannot explain or justify the charge , especially when it is all about making lucrative profits. Under contract law injured parties are not allowed to make a profit from an alleged breaches of contract. Damages are meant to put the injured party back into same position as if the breach had never occured. 
Some sly and devious parking companies will argue that penalty charges aim to cover a tiny proportions of the operational overheads , including the tracking down of motorists' addresses and the chasing the alleged debts. As regards pay-by-the-hour parking ,  this argument is totally flawed and represents yet another monstrous lie. Any sensensible business would set an hourly tariff price above its hourly unit cost to create a healthy profit margin. The hourly unit cost is calculated by taking the budgeted total overheads and dividing that figure by the estimated number of hours purchased , based on expected occupancy levels. Therefore , the operational overheads have already been covered and accounted for. This means for instance any alleged breach of contract , such as a 10 minute overstay, will not incur any loss other than the £10-15 mentioned above.
PCNs are not about compensation but pure greed for profit. A £70 parking charge demand is the equivalent of converting one tariff paying motorist into thirty. This behaviour is both obscene and immoral . So when an unwelcome and unwarranted PCN arrives through your letter box and you intend to fight it , it may be wiser to pay them £15 to cover their legitimate losses.  By stating that unless they provide a detailed breakdown as to how the other £55 loss has come about as a direct consequence of the breach, this cheque should end the matter. Moreover , at this point the company is under a duty to mitigate their losses and not incur further expenditure chasing up these manifestly unreasonable and unenforceable debts .

( However in cases where companies run car parks looking to charge overstayers who abuse the limited free parking on offer , they are entitled to use the PCN revenue to help contribute towards recovery of their operational costs. In addition to that the charge could well  include a deterrent element , especially if the car park is very busy , where spaces at a premium and where traffic space maximisation has become an essential business objective. See Parking Eye v. Beavis. )