Small claims division for the sticker damage to the fuel tank could be worth a try.
A magistrate could then decide whether the damage could have reasonably been avoided: eg Mr Plod could had attached the notice with tacks and a hammer & the effect would have been the same. Duty of care etc.
Costs about $120-$150 in NSW to run such a case yourself.
I took an insurer to the same court a few years back. Despite saying they would defend the case with vigor, the slack buggers never filed a defence...hence after 30 days got a default judgement in my favour. Got damages plus costs!
