When Louie Kritski first enters his apartment, he jiggles a sink faucet, shortly after which water explodes out from the drain. However, immediately after the second explosion, a close-up shows the water level is visibly higher than it was before.
When Louie first enters his slum apartment 5C there is a shiny metal light fixture hanging up in the area where the ceiling is leaking onto a puddle on the floor. He closes the front door, walks into the bathroom and the light fixture is still there. But in the next shot the fixture is now inexplicably lying on the floor in the water puddle. This is never explained.
Big Lou Kritski: Let me explain something to you, son. You fix this place up on Monday, Friday it's back the way it was. You put in plumbing, they put chicken bones down the toilet. Put in heat, they piss in the hot air ducts!