For example, a unit/building located in a zoning district that has now been changed to all single family.  

And there's a couple of banks in the same shopping district.

Or even go up to new or newer construction houses with high end finishes in great school districts for 150k and still cash flow.

I have found that the investors who are the most successful are those either buying in trendy areas like Lawrenceville, Strip District, Troy Hill, Near the casino, etc or those who are right on the river.

This parcel zoning is classified as General Use District Zoning, described as (page 54):The General Use District is established as a zoning district in which the principal use of land is for uses that are in harmony with residential, agricultural, and commercial development in Columbus County.

As a new investor it’s also challenging to ID what stage of growth for each of these districts.  

Tell them you will contact the district customer service representative about your denial.

I have been researching The Pearl District. 

It is in a excellent school district.

Because if you are single then you will be looking for night life, if you have school going kids then you need to consider good school district.