High Density Living, 2000 Years Ago: Inside the Roman Apartment Building

  See how pots strike and dint the sturdy pavement.

  There’s death from every window where you move.

  You’d be a fool to venture out to dine,

  oblivious of what goes on above,

  without your having penned that dotted line,

  of your last testament.

I can highly recommend Lindsey Davis' Falco series, murder mysteries set in Ancient Rome. She brings the city to life, it's remarkably vivid, and -- I promise this comment is on topic for this thread! -- Roman apartment living is threaded throughout the series and apartment building construction even forms a major plot point in one book.

I can't say more without spoilers. Excellent for "feeling" what Rome was like.

https://www.goodreads.com/series/42173-marcus-didius-falco

https://en.wikipedia.org/wiki/The_Mansions_of_the_Gods

I really enjoyed the film Fellini Satyricon because it shows a couple of regular guys on a crazy adventure after their apartment building in Rome collapses in an earthquake. Most other stuff about Rome/Romans follows leaders, generals, aristocrats, etc. so it was refreshing to see regular people.

And completely not based on reality, I also liked the British comedy series Plebs that also follows regular people living Rome. But it's just a way to show modern issues satirically, not really historical.

They called them insulae meaning "islands". They had no concept of fire escapes, and barely any plumbing (despite this image of Roman engineering). They really were the harris end of Roman architecture.