A quirky Brooklyn can collector who owns millions in Manhattan real estate better spare some change to fix up her dilapidated landmarked townhouse, the city said.

Lisa Fiekowsky, whose trash-filled car angered her Prospect Heights neighbors, faces fines of $5,000 per day because she’s allowed 451 Convent Ave. in Harlem to become run down, according to a lawsuit.

The 122-year-old building, one of five nearly identical row houses in the Hamilton Heights-Sugar Hill Historic District, has partially collapsed floors and joists, holes in the roof, broken and missing skylights and windows, and “significant ongoing deterioration of its important character-defining features,” the city and the Landmarks Preservation Commission claim in court papers.

Fiekowsky, who has owned the building for nearly 20 years, allegedly ignored an April warning letter to fix the place up.

The problems are worse than the city knows, claimed Fiekowsky, who told The Post she didn’t know about the lawsuit.

“The problem now is I have raccoons in the property,” she said.

She claims the damage arose after a fire in the building next door years ago.

“I’ve been very busy,” said Fiekowsky, who said she was forced to give up her garbage-filled jalopy after it broke down.