ReZoning to 2-family from 1(Used as 2-fam in the past)

[Ankan Basak]

Looking to buy a corner property already setup as 2 separate units. Bottom basement unit is above grade, got separate kitchen, bathroom and entrance. Was used once as 2-family back when, but since owner has turned into 1-family. Have to call zoning to find out if could be re-zoned into 2-family. Anyone has experience doing this in Philly, and how hard is it?