SAN FRANCISCO (CBS SF) — The San Francisco City Attorney’s Office is suing a property owner who allegedly turned the basement of an Excelsior District laundromat into a maze of illegal, unsafe units housing around 20 tenants.

The civil lawsuit filed in San Francisco Superior Court today names Melissa Mendoza of Hillsborough, her limited liability company Lexamark Building, LLC and Ernesto Paredes of Daly City, the building’s master tenant.

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Paredes allegedly rented the basement units for $300 to $900 a month and collected the rent in cash without a lease agreement or receipts, according to the City Attorney’s Office.

The lawsuit alleges that Mendoza and Paredes violated city codes, failed to address notices of violations and orders of abatement filed by the city and operated a building at 4680-4690 Mission St. that constitutes a public nuisance. In addition, it alleges that they violated state housing law and engaged in unlawful business practices.

The city discovered the unsafe conditions in the building on Christmas Day last year, when the fire department responded to a non-fire emergency call.

After seeing the warren of up to 20 rooms with two kitchens and three bathrooms, only one of which had a shower, firefighters called in fire inspectors, who cited the building for numerous code violations, including inadequate and blocked exits, a lack of illuminated exit signs, construction without permits and unsafe conditions.

Officials said there was no garbage collection for residents or running water, hot water or heat, the ceilings and pipes leaked and wiring was exposed in the walls. Additionally, there were no windows and only one exit.

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“This building was a firetrap,” Herrera said.

“The living conditions were not only appalling and illegal, they were extremely dangerous,” City Attorney Dennis Herrera said. “These people were basically stuck in a dungeon. I don’t want to think about what would have happened if there had been a fire down there.”

On Feb. 14 the fire department ordered the property evacuated due to the unsafe conditions, and ordered the property owner and master tenant to pay relocation costs of $4,262 per unit to the tenants.

City officials worked to find housing and support services for the residents, many of them immigrants, who ranged in age from 12 to 72 and included several families.

The lawsuit is seeking a court order preventing the unoccupied areas of the building from being used until it is brought up to code, restitution for the tenants and civil penalties, as well as attorney’s fees and costs.

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