No, they are not. There are more single family twin homes on that block than there are duplexes. There is one for sale actively and one that has expired but still might be available. If you are interested in more information please do not hesitate to email, or call me.
Maurice Rollins (267) 258-2078
Exit Realty "The Tri-State Group"
1080 N. Delaware Ave
Philadelphia, PA 19125