the great thing about Philly is the variety of neighborhoods and opportunities to be had here. Philly is known for its education and hospitals and you can do very well with student housing here. For example, North Philly by Temple University is a wonderful place to get into; however, the boarding neighborhood can be a little undesirable and breaking into the Temple market is difficult due to higher cost. TU students look to feel safe, so they look for living situations closer to campus, but of course for us investors, that drives the price of homes up in that location. Take a look at all the colleges if you decided to go that route, and really go to each neighborhood to get a true feel of each section.
Brewerytown is looking poised for the next boom, it is also in North Philly but it is more south, closer to Girard Ave which is a integral part of the city. The Girard trolley runs from Brewerytown to Fishtown. Fishtown is wonderful, and whoever got involved in the Fishtown area before its resurface of recent years is a savvy investor and most likely sitting pretty. Brewerytown right now is reasonably priced, but with the spill over from the Fishtown, Northern Liberties market saturating the east, treads within the last few years suggest the movement towards the west, I.E Brewerytown. Another great selling point of Brewerytown is that Fairmount is just south of it, A JEWEL of a neighborhood of Philadelphia.
Something else to consider is Kensington. Kensington is currently a rough neighborhood and has been but so was Fishtown. Kensington is by Northern Liberties and Fishtown on its southern boarders, giving it a prime location for a revitalization.
Point Breeze in Southwest Philly is also another area to consider. Hope this helps and best of luck!