I'm reading a fascinating book that tries to understand the archaeological evidence of ancient Ostia in terms of the Roman legal code.
There are strange gaps in our knowledge, things that really matter to us but that nobody thought to write down. The Romans had lots of slaves: where did they sleep? Where did they keep their stuff? We don't know.
But there are some things we do know, because real estate law was always a nightmare. We can figure out, for example, that the firemen owned some shops and rented them out, because the shops would not have been up-to-code unless they and the firehouse were jointly owned.
In Rome, property rights extended from the ground to the bottom of the sky. Except, if your neighbor had an ocean view, it was illegal to block it.