we live on the top floor of a building with 6 units, 2 on each floor. there is a small porch out front on each floor with a door that opens to the stairwell. today i came up the front stairs and it smelled awful- like dog. dogs are not allowed in our building but the people across the hall recently got a tiny dog, <5lbs, and they keep crating it out there. they leave it out there most nights, even one night when we had a frost advisory, and today it was in the mid 80s, the front porch gets hot and they left it crated out there all day. i'm assuming there is dog waste in the crate with it from the smell in the hallway. i don't care that they have a tiny dog, i care that they seem to be hurting it and that it smells and yaps at my cat through the window (he has pancriatitus and it acts up when he gets stressed). DH is friendly with the husband & the wife has gotten in fights with other people in the building, like craaazy fights that DH has had to break up, so i don't wanna get on their bad side.

what would you do? tell the landlord? ask them to keep it in their apartment? ignore it?