David Stover, of Southern Maine, is the owner of Saint Nick's Chimney Service. Saco, Maine — With a brush rod in one hand and a grin in the rain, David Stover climbs the ladder like he’s done it a thousand times before. Below him, his mother Sherrell runs the vacuum inside the house, her steady rhythm matching his scraping above. Together they form the heart of Saint Nick’s Chimney Service , a Southern Maine company that has been keeping hearths clean and safe for more than