One stack, three households, and only one of them called you
A rowhouse divided into flats runs its waste and its water through shared pipe, so a repair upstairs becomes an event for people who never hired you.
The owner on the second floor calls about a kitchen line that will not drain. The pipe it feeds passes through a basement belonging to somebody else, and the valve that has to be closed takes the water off for every unit in the building.
A repair like that is a building event rather than a household one. Before anything is recorded, the household whose space appears has to agree, and a yes from the owner who called you is not a yes from the neighbor whose basement your crew is standing in.
It also hands you an audience most plumbing jobs never get. The people whose water was off all day genuinely want to know what was wrong, and a short clip of the section that came out answers a question the whole building has been asking in the stairwell.
Keep the neighbor's half of the basement out of frame. Their storage, their door, their bicycle. They agreed to a technician in the room, not to an audience.
In the old core this is ordinary rather than unusual. Rowhouses in Shaw, Petworth and Columbia Heights were carved into flats decades ago, and the plumbing was divided long after the walls were.