I live in the greater Maryland  area.

However, if you choose to stay there for a bit and sell you'll get the first $500K of profit tax-free if you've lived in it for at least 2 out of the 5 years prior to sale.

City recently did a building inspection and we noticed the tenant is smoking in the unit (cigarettes and marijuana), food waste everywhere leading to building pest issues, and there are 5 people living there now (3 adults and 2 kids).

Keep the current investment and buy another house hack to live in.

I have improved fair rental value and value by increasing the kitchen size; adding an island tearing down walls between the kitchen and dining area and living area, etc.It all depends on the particular property. 

Buy where you intend to live, where you know the areas best.

Quote from @Marc Zak: In the market where I live (San Diego), appreciation has been strong and many predict it will continue to appreciate in the long term.However, with current interest rates (6% at best) and property tax (2%), the annual cost burden is 8%.Am I correct in saying that appreciation has to be above 8% annually (plus whatever my maintenance and vacancy costs are) for me to make any money in this scenario if the property is cash flow neutral?

I live in the Washington DC area, and I would love to connect with anyone willing to. 

You'll need a contact who lives in Philadelphia for a rental license now to put down their contact info for the city.

I live approx 60 miles north of Atlanta.