In a city where it is notoriously difficult to find a flat -- especially on a low budget and without the right paperwork -- many rooms that once served as domestic helpers' sleeping quarters have been turned into apartments for rent.
It is borderline illegal to rent out these micro-apartments, typically wedged under a rooftop, as they measure less than nine square metres (100 square feet) and often lack proper ventilation.
But many people simply cannot afford any better, and some, like receptionist Ivan Lopez, face other barriers.
"I don't have a guarantor, no relatives in Paris, and I have a foreign accent," says Lopez, a 35-year-old of Mexican origin who rents a room measuring just 6.8 square metres for 370 euros ($415) a month.
Repeatedly turned away by rental agencies, he has been unable to find better lodgings for eight years.
Lopez's bed, which doubles as a sofa and a storage space, is squeezed against an old fridge and a tiny shower stall.
"I work the night shift, and in the morning it's really hot when I get back. I can't sleep in here," he says.
Relic of bourgeois life
Flats that were once sleeping quarters for domestic workers are a relic of bourgeois life in the 19th and early 20th centuries when they were referred to as "chambres de bonne" -- maids' rooms.
Astonishingly, they still fetch sky-high prices of up to 11,000 euros a square metre in Paris's well-to-do neighbourhoods.
Victoire Ratrimoson, 67, was a modern-day version of the traditional "bonne" when she moved into her sixth-floor perch in the chic northwest in 2011.
Originally from Madagascar, she took a job as a domestic helper for a family living in the building. But the family soon moved out and tried to force her to leave.
"They told me, 'We don't require your services anymore. We've found someone who charges 400 euros a month," Ratrimoson says as her eyes well up with tears.
For lack of anything better, Ratrimoson is clinging to the tiny space measuring 7.5 square metres, with no ventilation or heating. "I don't really live here, I just sleep here," she says, standing in a room with shelves packed right up to the ceiling.
Like Lopez, Ratrimoson is holding her breath in the hope that authorities will officially declare her home to be uninhabitable. That would make their expulsion illegal and in turn force the owners -- or
the state -- to find them proper housing.
According to the Abbe Pierre Foundation, a French NGO that fights for the rights of people living in substandard housing, authorities are dragging their feet on the issue.
"Today, there are some 7,000 domestic helpers' rooms that serve as people's main place of residence, and which measure less than nine square metres. Still, in most cases, the state has not declared them uninhabitable," says the foundation's Sarah Coupechoux.
The government's health agency for the Paris region says that around 50 of these rooms are declared uninhabitable each year, and the number is on the rise.
Agency official Emmanuelle Beaugrand says an administrative court decided in 2013 that insufficient size is not the only criterion for declaring a space unfit for habitation.
"For a room measuring seven to nine (square) metres, we no longer issue such orders systematically. Other criteria need to be met too, such as inadequate ventilation or layout," she says.
Housing deputy at Paris city hall Ian Brossat pledges to put in place a plan "very soon" to reform these spaces.
Albert Verdier took 15 years to find a better home than the 6.5 square metres he occupied for 350 euros a month.
The 56-year-old works two days a week at the parliament building canteen and the rest of the week as a security guard. Now he can actually cook his own meals in his 19 square metres -- a palace
in his eyes.
"When I first moved in here, I thought, 'This can't be. I must be dreaming'," he smiled.