Compared to the rest of the Philadelphia market, the Northern Liberties - Fishtown region has lower rates, so you should have no trouble finding a great deal in this depreciated region.
In the last 90 days, 2 listings have been made available, which means leases are probably going fast. You'll want to be prepared to make an offer immediately. There aren't many listings below 2,000 square feet available, so finding a space for a small business might be tough.
Even though the median size is 3,700 sqft, there are still 0 new availabilities below 2,000 sqft. Most buildings in this market are around 4 floors. Most buildings in this area were built in 1950 and are Class B.