Private parking firms cannot send bailiffs to your home, becaust they would need a court order! They can however send in debt collectors, who must tell you when they are coming and have as much right as the ice cream man taking you tv or whater, can only phone or write to discuss debt and they cannot repeatedly contact, harass or during unsociable hours.
A simple way of dealing with a debt collecter, is deny you owe them debt. A debt collecter would then stop contacting you as they a regulated and may be considered harassment, to which you can report them.
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