Austinmer resident Em Thompson, who wants to upgrade her white 2013 Land Rover Discovery, was appalled when she discovered it had been plastered with a printed A4 document demanding she sell the vehicle outside her own house.
"We don't want this stretch turned into a f***ing car yard!" the letter reads.
The mother-of-two told Yahoo News she lives on a side street around the corner from where the car was parked on Lawrence Hargrave Drive, which is a main road connecting Wollongong's northern suburbs.
"We parked there because it was the least obstructive place to people or business. That's why I was so angry and upset with the letter," she explained.
Images shared with Yahoo News of where Ms Thompson claims the car had been parked show it wasn't in front of any houses.
"So I don't understand why the note was even written," she said.
"Angry" and "upset" by the note, Ms Thompson took to social media to expose what she describes as "poor behaviour".
"My main focus was to share it to the group to make it known that the behaviour was appalling and the language abysmal, and after all it wasn't on or blocking any private properties," she told Yahoo News.
"So I figured exposing the poor behaviour would be best for hopefully eliminating it."
She began the post to a local Facebook group by cheekily thanking her neighbour for the "sweet note".
"Thank you so much to the lovely human being who left me such a sweet note," she wrote.
"FYI it's not in front of anyone's house, it's actually on a stretch of road where there aren't any houses and my house is also just down the road from where it's parked," she added.
Locals slam note writer
Ms Thompson's post struck a chord with fellow residents, who lashed out at the anonymous note leaver.
"I'm so very sorry that you have had to experience such unkind and cowardly behaviour. Nice people include their name and address when corresponding via letter," one person commented.
Another slammed it as "so aggressive".
"Obviously someone has nothing better to do than be a sook," someone else added.
Others labelled the angry neighbour as a "Karen", with one Facebook user commenting: "To be fair maybe you parked it where Karen wanted to park hers."
Road rules on car owner's side
Many backed Ms Thompson's parking decision, with one woman clarifying: "No one owns the spots outside their houses".
"As long as you don't park in anyone's driveway entrance and it's not a no standing zone, it's a free for all on the road to park. No one owns the spots outside their houses, it's a privilege," she wrote.
Others were amused that someone had gone to the effort of printing the note.
"Old mate probably has heaps of agro notes all pre-printed for any occasion," someone commented.
There are no laws in NSW relating to cars that are advertised for sale being parked on roadsides.
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