Seeking insight on zoning in Philadelphia

[Jonathan Gomez]

I am in the process of searching for my first investment property. I do not know much about zoning. I am currently looking at a property that is set up like a duplex, without the zoning being changed accordingly. This property was renovated and rehabilitated within the past 2 years. Is the fact that it's not zoned as a duplex a big problem? Is it reasonable for me to use that fact as a negotiating point to get them to zone it properly before I consider investing in it? What have some of you experienced as a result of owning rental property that wasn't zoned correctly?