Most of the urban poor and working class would have lived in Insulae, apartment buildings. Having a proper house in the city was much more the domain of the middle and upper classes. Despite the label of the image, the term ‘villa’ is generally reserved for the (often secondary and luxurious) rural residences of the elite, while ‘domus’ usually is used to refer to smaller houses in the cities.

I always loved these buildings. Don’t know why but they are just so cool to me.

There’s cutaways of numerous villas in Pompeii.