The survey was carried out by British TV show This Morning which interviewed a landlord who admitted he frequently offered rooms to women for free in return for sex, insisting he was doing nothing wrong and sparking outrage on Twitter.
"This is AWFUL. The woman do it because they are desperate and these men are preying on that and using their power. Sick. #ThisMorning" said one woman on Twitter.
However the rise in sex for rent arrangements is not confined to Britain's capital, rogue landlords in Wales are also offering free or cheaper accommodation in exchange for sexual favors.
Wales' national broadcaster ITV Wales has seen posts online from a man advertising a free room in Cardiff "for a female with whom I can come to an arrangement." Another advert for a room in Newport said, "rent greatly reduced in return for favours."
An undercover journalist later secretly filmed the landlord offering a one-bed annex, free of charge in return for sex once a week.
Former justice secretary David Lidington said rent for sex offers could breach the Sexual Offenses Act.
"An offense is committed when a person offers accommodation in return for sex, as they are inciting/causing another person to have sex with them in return for 'payment'," he told Hove MP Peter Kyle in a letter.
Housing charity Shelter wrote a blog in 2016 about the rise in sex for rent after receiving a tip-off about a classified advert on Craigslist UK targeting homeless women and offering a free room in return for sex.
"Through these adverts, men are intentionally targeting desperate women who feel they have no other options — and women who may already have experienced sexual or domestic violence," the blog states.
"This isn't just bad in taste or 'creepy'. It is a dangerous attempt to establish deeply exploitative relationships off the back of homelessness," according to Shelter's blog.
Two years later and it appears unscrupulous landlords are no longer just preying on homeless women but any women looking for a room to rent.
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