After a sports injury, Esteban Serrano owed $829.41 for a knee brace purchased with insurance through his doctor’s office. He says he found the same kind of brace selling for less than $250 online.

After a sports injury, Esteban Serrano owed $829.41 for a knee brace purchased with insurance through his doctor’s office. He says he found the same kind of brace selling for less than $250 online.