Hi Uberonwer
I think Kaindub makes some reasonable points; in what way is the ‘owner’ affecting the building’s security i.e., ‘sabotaging’? What sort of damage to the ‘security’ has been done and what makes you think they are doing it ‘deliberately’? As Kaindub suggests, best first to communicate with the ‘owner’ you think is damaging security or perhaps do a group communication notice to ALL owners instead. Or as you have indicated, in original Flatchat post – have you actually ruled out if the damage to the ‘security’ is being done by previous old resident and rather than an owner?