You need to decide what area of RE investing you want to concentrate on.

Do you specialize or concentrate in a particular class of property?

I understand I might not get that lucky but unless the house is in the worst neighborhood ever should I concentrate on the right flip for me and not worry if it's not located in my target zip code

Tom, Instead of concentrating on a number of houses to buy (or number of doors - this is what I would advice everyone to do instead!)

I think for starters, I want to concentrate on south central PA, because it is close.

Once you have built your reputation as a "Neighborhood Specialist" then you can concentrate on becoming a "Listings Only" Agent.  

Typically, a licensed agent or a current property owner with experience in the product field you are concentrating in will be the best help.

If the property you're buying is owner occupied, the investor concentration doesn't come into play because you will improve the investor concentration. 

Have you identified a niche in real estate you want to concentrate on?

In terms of the strategy, pick one the interests you the most at this time and concentrate on it until you perfect it, then move on to add another strategy, and etc...