.
How many cars are we talking about ?
Post the letter. Redact if necessary so we can see it.
Start legal procedure against town. Minimal cost, probably just a filing fee. Then keep delaying and postponing proceedings on your side to buy time while you figure what to do with the cars.
Maybe put up a wood privacy fence ?
Put cars under a Pop up canopy with sides ?
Push them all together and cover with a tarp(s).
Put up
No Trespassing signs.
Fly your own drone over their property
repeatedly while they're home and state that it's to see if they are in compliance and that you're only doing it for the good of the community.
Don't throw the towel in yet...
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