Ian Hersey had lived in Brooklyn for more than 30 years, including the past dozen or so in Prospect Lefferts Gardens. He rented a two-bedroom in a two-family house, often sharing it with a roommate. Last year, the landlord announced that she’d be raising the rent, which had been far below market rate, from $1,750 to $2,400 a month.

It was just the catalyst Mr. Hersey needed to finally buy a place of his own.

“I had a chunk of money and wanted to use it wisely,” said Mr. Hersey. “It seemed to be the next right thing.” Besides, friends of his who owned their homes usually had lower monthly expenditures than those who rented.

The landlord gave him six months to find a new place and move out. Despite his long history in Brooklyn, Mr. Hersey, a 51-year-old actor, acting teacher and director who focuses on Shakespeare, knew that with a budget of $200,000, he would not be able to stay in the borough. He was hoping for a sunny one-bedroom co-op somewhere else in the city.