After a 90-day “elimination” period (often partly covered by Medicare for people whose need for extra care is hastened by a stroke or other medical emergency), the policy covers all assisted living, community and home care.

Its benefits, however, only increase at a 3 percent annual rate, which is less than the typical increase in nursing home costs. And to qualify for the discounted rate, not only must the applicant be in reasonably good health, but he must apply with his spouse or partner.

Indeed, one crucial consideration in determining the cost is medical history. You will pay more if your health is less than ideal. A “standard” rating for this policy could result in a premium perhaps 20 percent higher or more.

Moreover, keep in mind that, unlike health insurance in the Affordable Care Act era, companies can deny long-term care coverage based on your medical history. If you have had maladies such as diabetes, Parkinson’s disease or a stroke, you may not qualify at all, according to the American Association for Long Term Care Insurance.

Ms. Cheng recommends that a potential buyer work with an adviser to drill down into both the policy and insurer before purchase. You want an insurance company that is going to stay in the business, which means making sure they are experienced and financially sound. Dozens of companies have left the business because they were not making money and underestimated the number of claims.

You also want to consider how the insurance meshes with your overall financial plan.

“Many times folks look at the cost of care in their area and then decide that it’s too expensive to even consider long-term care insurance,” Ms. Cheng said. “Looking at the cost of care is a great starting point, but it’s more prudent to adopt a holistic and integrated approach, then design a policy around your needs.”

Deciding to buy a policy may require hours of discussion with professional advisers before you make a move. Among the questions: Do you need to insure for things like adult day care, home care or assisted living, or will you have the resources to pay for these services from your savings? Have you done estate planning to determine how much you plan to leave behind?