When you look on zillow it looks like values are trending down.  

It seems like a trend that is on the way out.

Too bad we don't have a resource that provides a macro economic comparison or ranking by zip code on such things as house sale turn-over, prices, trends, job growth, population growth and inventory levels for things like lots, new homes, etc.

Maybe, keep them updated on market trends, interest rates, anything that might affect their neighborhood and the price they can get for their home.

so I did them site unseen.. then flew out there and checked it all out and said what the heck  this is one of the hottest market s in the US.

I just finished reading through this year's RE trends study done by Urban Land Institute and PwC.  

The Rental trend remained bullish in January 2015 with rents inching up in most metropolitan areas of the US when compared to December 2014.

I see the population, demographics trends to continue into 2020.

Was wondering if that trend has continued throughout 2014.Are they still accumulating?

There are comps to support that number.Also your neighbor listed his at:3211 Rockview Dr, Lithonia GA4 /32,491sqft1,075/mo0.43/sqftand his is 200 sqft larger than yoursif you do a $999 special it should fly off the market.also note the rent trends have not been favorable in that area, for the past few months they've been trending slightly down.