“We are all afraid of the roof caving in,” said Ms. Moller Kareman, who had to pay $20,000 to fix the building’s out-of-commission elevator when she was first hired. “The elevator guys said we don’t even have parts for this anymore,” she recalled.

HB Studio owns its three West Village properties, all bought in the 1950s and ’60s. It, too, has undergone some belt tightening. Founded by the actor Herbert Berghof, who was joined later by Ms. Hagen, the school and theater collective established a reputation for quality acting classes (its alumni list includes Robert De Niro and Jessica Lange) at famously low rates.

“When Herbert Berghof died in ’90, I think it was still $5 a class,” said Edith Meeks, HB’s current artistic and executive director. But even by 2004, when Ms. Hagen died, HB had only marginally increased tuition. Modest, incremental fee hikes were just not “enough to catch us up to the real expense of running a nonprofit and managing three buildings in the 21st century,” said Ms. Meeks.

So in 2013, for the first time in its history, HB streamlined its curriculum and significantly raised its bargain-basement prices as part of a “one-time adjustment-to-market,” said Ms. Meeks, who confirmed that enrollment is stable but nowhere near the numbers it had in the 1960s. “We were super affordable, and now we are affordable.”

The change was made with a heavy heart, said Ms. Meeks, who admitted that young actors are affected by New York’s real estate and job market just as much as the institutions training them. “They commute from farther and farther away to study with us at HB; many of them have crushing college debt and they struggle to stay employed and to have enough flexibility to continue their creative work,” she said.

Image The Neighborhood Playhouse opened its school at the Henry Street Settlement in 1928. In 1947, the Playhouse moved to East 54th Street, where it has been ever since. Credit... Sara Krulwich/The New York Times

For acting schools that pay rent, the situation is even more tenuous.

The Atlantic Acting School moved into the Chelsea neighborhood 26 years ago, when “no one wanted to be there” and “rent was cheap,” said Ms. McCann. With a pedigree that includes the playwright David Mamet and the actor/director William H. Macy — not to mention a thriving children’s program, a connection to a professional theater with 12 Tony Awards, and even a coveted affiliation with N.Y.U. — it would seem that the school would have a rosy outlook.