The Brief Frentz & Sons Hardware Co., Inc. in Royal Oak is winding down business after more than 90 years in business. The owners of the beloved Royal Oak hardware shop said they are putting the property up for sale. Having been in business for nearly a century, a well-known name in Royal Oak small business lore is winding down operations. Frentz & Sons Hardware, located on Main Street, will close up shop, the owners say. Big picture view:After more than 90 years in business, a beloved Royal Oak hardware store is looking to wind down operations.