If you really want to invest in a great neighborhood that's still "up & coming" I would highly recommend you look at SWCC (Southwest Center City) a.k.a. the "Graduate Hospital" neighborhood ("G-Ho" sometimes for short).

#1 it's not an unreasonable commute for you...
http://maps.google.com/maps?f=d&hl=e...7&ie=UTF8&z=14
I'd call that a good healthy walk on nice/energetic days, and on lazy/bad weather days, you could take the #17 bus (which has fantastic service), connecting with 3 different other buses, according to SEPTA's trip planner...
http://airs1.septa.org/bin/query.exe...28263&OK#focus

I just did a quick search & there are tons of places for sale for under $300K in this zipcode (19146)...
http://www.realtor.com/map/search/se...=2&bth=2&typ=2

SWCC is just a 10 minute walk from Rittenhouse Square (arguably the nicest part of Center City) & all the wonderful surrounding areas, while still being very affordable.

When I referred to it as "up & coming" what I mean is, it's still a bit rough around the edges right now, but undoubtedly well on it's way to becoming one of the best investments I personally think you could make in Philadelphia right now.

On top of that, though the real estate market really hasn't crashed here like it has in much of the rest of the country, sales have slowed down a bit so there's a lot out there to see, which means you should be in a very good position to negotiate right now.

In the 2 years my husband & I have been living here we've seen a tremendous amount of positive change, and there are definitely no signs of it slowing down.

So for all those reasons (and more) that's why I'd say, if you have the money to invest now, I would go for it. We just love it here & I seriously don't think you could go wrong. Do it now!

Okay, that's the end of my shameless plug for what I think is a terrific neighborhood.

Good luck & let us know if you have any other questions.