I'm currently writing my bachelor's thesis on something related to Machiavelli (well I should be at least, but here I am, and we all know this isn't exactly a sign of me being disciplined and productive). Some kilometres south of Florence there is a small town called Percussina, in there is a house called "the Albergaccio" which was where Machiavelli moved when he hit rough times and is still open to visitors today. Of course, one must be wary of what it looks like today, as it is a tourist attraction and a fancy restaurant and offers wine from Machiavelli'v vineyard and stuff like that, but it is likely as close to a "normal living situation" from the 15th and 16th century as one can get today.
Machiavelli, while known throughout the world in the present, was what we might consider upper middle class today during his career and struggled with poverty when that ended. He not at all famous or wealthy or powerful, although he did gain some recognition for his literary and theatrical works almost exclusively within Florence late in his life. While he had a lot of responsibility thrust upon him, he was never formally made a diplomat and his stipends were rarely enough even to cover his travel expenses in the service of Florence. His correspondence bears witness to the fact that scrounging for money was no small part of his life. When the Medici returned to Florence in 1512 he lost his old job working for the chancery in Florence and after a brief spout of incarceration and torture moved out to the Albergaccio which was a family heirloom and likely a lot safer than remaining in Florence, but mainly the reason he went there was because he had no more income and out in Percussina he was able to at least somewhat support the family with what the land could offer, like selling thrushes he would catch in traps as one of his more famous laters vividly describes*. The point of me mentioning this is to underline that he was really scratching the bottom of the barrel trying to survive, this is certainly not the diplomat-Machiavelli residing in kingly courts in the service of the Republic of Florence.
Ultimately though, this was clearly more of a country-estate, albeit modest, than an urban, low-income housing situation. His house in Florence might be closer to that, but it no longer stands, and by all accounts seems already the worse for wear during Machiavelli's lifetime - his latest Biographer, Alexander Lee** (whom I wholeheartedly recommend) gives a description summarizing everything he could gather on it, it was a two-story affair built around a courtyeard and seems to also have been home to some nephews and uncles. I am also dimly aware of there being a drawing of this house. So far I was unable to find it, but perhaps someone else is more resourceful than I am.
Of course, living situations were a lot worse for many people, but to my knowledge, at least when asking about extant buildings, that's about as far down the social ladder you can go.
*Letter No.137 in: Gilbert, Allan: The Letters of Machiavelli, Edited and Translated by Allan Gilbert, Chicago 1988.
** Lee, Alexander: Machiavelli. His Life and Times, Croydon 2020.