No one had to tell the Buchanans about the risk. Dianna, 51, survived a bout with cancer 15 years ago. Keith, 48, has high blood pressure and takes testosterone shots. They live in Marion, North Carolina, and make more than $127,000 a year from the small IT business Keith runs and Dianna’s job as a physical therapy assistant, with some additional income from properties they own. That puts them in the top fifth of households by income.

But their insurance premium was $1,691 a month last year, triple their mortgage payment—and was going up to $1,813 this year. They also had a $5,000 per-person deductible, meaning that having and using their coverage could cost more than $30,000.

What sealed the deal was when Blue Cross and Blue Shield of North Carolina and the major hospital system in Asheville, Mission Health, couldn’t reach an agreement, putting the hospital out of network. Keith Buchanan compared the fight to a cable company battling with a broadcaster over what channels to carry.