Actual home trades are more common with investors and are rare in those instances. The main people doing them are higher level investors and they are trading "units" - as in, they aren't even referring to them as homes anymore.
Another common "trade" is a 1031 tax exchange. Again, this can only be used on investment property, but is a great way to "trade" up or down to a home, tax free. Please contact me about this if you are interested.
The big thing here, is the market. Even if you find a willing seller, you would have to both agree on market prices for your homes. In your case Snellville, is a bit slower than Dunwoody and Duluth. Of course, you'd be expected to bring the money for the difference in the homes and in a trade scenario, that would most likely have to be cash (if we're talking very strictly a trade).
What is more likely to happen is that you agree to "trade" but then sell your homes to each other. That will make more sense and be "cleaner." Plus it allows for financing.