There are also several major hospitals in the area which make it a hub for travel nurses, if STR/MTR's are also something you would consider.  

Investments in mixed-use development, office buildings, and residential areas have attracted more residents and businesses, positively impacting the real estate market.Strategic Location and Infrastructure:The strategic location of the Lehigh Valley, bolstered by infrastructure like the Lehigh Valley International Airport, makes it a hub for transportation and logistics.

I think, yes it has appreciated and there is way more appreciation to come as Miami and Broward become a major financial hub and metropolis of the South.

All of that being said, from an investor's standpoint, Philadelphia is one of the lowest priced major cities in the Northeast, it has easy access to other major cities and industry hubs (NYC and DC), amenities are amazing (access to hospitals, beaches, parks, rivers, museums, restaurants, etc.) and the market is booming (Expats from NYC and other high priced cities). 

Those areas provide a great bang for your buck by California standards and are small towns that are close enough to major business hubs.

I actually grew up in a neighborhood like this that is now the Hipster hub of SD.

Transit-Oriented Developments (TODs): Transit-oriented developments are mixed-use properties located within close proximity to transportation hubs.

With RTP, Duke, UNC and NC State, and IT hub, Pharma hub, this place is not going to slow down. 

Atlanta is also one of the top 5 tech hubs in the country, with companies like NCR, Honeywell, Silicon Valley-based Apple and Google parent Alphabet, and Microsoft calling the city home.

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