Raissa Fomerand grew up in Williamsburg, Brooklyn, and spent her early adulthood as a young striver in Carroll Gardens and Brooklyn Heights. She remembers those days fondly. So when her children were grown and out of her colonial in Larchmont, Ms. Fomerand, 71, divorced and retired, wanted to move back to New York City.

“Lots of things come easily in the suburbs, but what doesn’t come easily is the intellectual stimulation of being in an interesting neighborhood,” said Ms. Fomerand, who has lived in Westchester County for nearly 30 years. “I’d like to live near the Metropolitan Museum or a place of culture.”

A year ago she started hunting for an apartment in Manhattan, and the search proved unnerving.

Prices in Manhattan, as she put it, had “hit the ceiling,” and “everything was minuscule and expensive.” With the price of one-bedrooms in the more sought-after neighborhoods approaching — or surpassing — $1 million, she counted herself lucky when she heard of a studio on the Upper East Side for a bargain of $400,000, but then found out it had little more than 500 square feet. The two-bedroom apartment in Mamaroneck, N.Y., where she has been living since her divorce cost less than half that and has more than double the space.