I am in R4 zoning, which does not rule out STR's in almost all cases of municipal code I have looked into.

FHA requires inspections, seller-paid repairs to code, everything must have been perfectly permitted).

@Holli HaddicCheck with municipal/township if allowed and the codes requirements 

Building codes and older homes can change the equation as well.

I am looking for a zip code and/or neighborhood breakdown for my single family and multi family investment property search.

Mesa is a large city and it's best to get zip code specific whenever you're trying to determine how the real estate market is doing. 85201, 85202, 85210, and areas close by are some of the hottest in metro Phoenix.

Dear BP, I have a wholesale opportunity in the 36117 zip code.

As others have noted above, although looking at an area and zip code can give you a general idea of what to expect, you definitely need to look on a street by street basis.  

I have limited to 4 zip codes for multi family only.

I have heard of people renovating basements so they can make it into a rental.Make sure when renovating a basement that it can meet Massachusetts Building Code and the Minimum standards of fitness for Human Habitation otherwise the tenant can take advantage and not pay rent.