If the property is occupied, knock and ask the tenants who is the landlord or property manager for the building. If that is to direct or if the property is vacant, check the city's public record by going the http://www.phila.gov. The owner's name will be listed there. If you need assistance feel free to contact me at 215-687-2629.
Samantha Weekes Realtor
Exit Realty "The Tri-State Group"
1080 N Delaware Ave Ste 200
Philadelphia PA 19125