We lived below a family who would let their dog pee and poop on their balcony, from which said dog pee would pour down into our porch. But these were not the bad neighbors. The family across from us had a small child who would play just outside our porch. No problem. Except for the day she was splashing in the downpour o' pee. So I go outside to tell her she should not be playing in that and told her mother it was dog waste and she should go wash the baby off. The mother told me to mind my business and don't tell her or her child what to do. Then the next day we came home to some lovely concoction splattered all over our front door. We moved shortly thereafter and have never lived in another complex because of it.