Diana Thompson thought she could con tenants in her unlicenced Wembley home, lie about her council tax payments and deceive private housing services.
But the rogue landlady, who owned a two-storey house in Barn Way, has been fined more than £20,000 by Willesden Magistrate's Court.
Brent Council housing enforcement officers received a tip-off from council tax officers that Ms Thompson was trying to claim a single person's discount when in fact she was living in a home that she was renting out to seven other people.
When they raided the property in July, she lied saying she was related to the landlady and that the first floor of the property was owned by another landlord.
On April 25 she was ordered to pay £15,000 for failure to licence her property and £5,000 for failing to comply with fire regulations. She was also ordered to pay £4,678 in costs and a £170 victim surcharge.
Cllr Eleanor Southwood, lead member for housing and welfare reform, said: "Rogue landlords will not get away with pulling the wool over our eyes. If a landlord or agent is breaking the law, we'll find out and we'll hold them accountable.