Though some at-home programs date to the 1990s, there are still very few. Across the country, nearly 2000 C.C.R.C.’s, mostly nonprofits, serve about 745,000 residents. Only 32, in about a dozen states, have added at-home programs.

But more senior living organizations are considering this approach, a possible answer to a perpetual conflict: Older Americans are very likely to need long-term care, but often loathe the thought of leaving their homes.

“Most people want to age successfully in place; they don’t want to transition to a community,” said Kevin Ahmadi, who heads Senior Choice at Home, connected to Gulf Coast Village, a C.C.R.C. in Cape Coral, Fla. “We believe there’s a strong future for at-home programs.”

To enroll, applicants must provide years of medical records and extensive financial documents showing that they’re healthy and can afford the fees. Progressive neurological diseases, like dementia or Parkinson’s disease, will disqualify applicants.

“We assume they won’t be needing any services for at least five years,” said Cecily Laidman, executive director of Springpoint Choice. But that need could arise in 15 years or the next month.

Such programs work financially, Ms. Laidman said, because many members enroll in their 70s, instead of waiting to move to a community in their 80s. They’re paying into the program for a longer period than if they had moved into a facility, allowing the programs to invest for members’ later years, when they’re more apt to need care.