Is 16 Millstone Way, Harpenden for sale?

Not with open for offer: we hold no listing, and can't see whether it's advertised elsewhere. You can register interest whether or not it's for sale. A home doesn't have to be advertised for its owner to decide to sell. You join its queue, which shows when you joined and never who you are. If the owner claims the home here, they see that someone registered, and when.