I recently acquired an older double wide with aluminum siding.  

The harsh reality is that many (not all) of the designated "protected groups" are such because they are high risk for a wide range of reasons.

Hi @Laura Richards,Note that on the FAR/BAR As-Is contract that is currently being widely used, there is a spot for the seller to sign on Page 11, Line 586 formally rejecting your offer.

I am still early in my research, and I am currently looking nation wide for the the best area to focus on.  

I'm just starting out myself and like to network to keep an "inventory" of what others in my area are looking for in case I run into a deal they might be like.I spend a lot of time in homes and driving around the state (I work for a state-wide GC) so get to look a lot of places.

which offer such a wide variety of investment opportunities and all have unique character. 

Fells Point, Canton and Federal Hill, all being close to the harbor, are older 'closer' neighborhoods with 10-foot wide rowhomes and narrow streets and alleys, but so much charm.  

I arrived to the condo to find the door unlocked and wide open.

I am also keeping my eyes wide open for a possible flip as this is in my wheelhouse. 

You've mentioned a couple of general strategies, but no plan of how to get to your goals...which you also haven't stated...and no, having a wide ranging number of "25-50 units by the time you're 50" isn't a set goal.You need to reverse engineer this, starting with your financial goals...not some arbitrary number range that has no financial definition.