What Bikerjulio said. You did not specify which trim model or whether it's aluminum or carbon. The link MMsRepBike posted is for a high trim carbon model, so it's misleading.
There are/were many different levels of Synapse. 2006 was the first year for the Synapse. It improved tremendously over the years. I bought a 2006 Synapse Alloy 4 new for $850 which I sold in 2012 for $400 on eBay and was surprised the auction went that high back then. It is definitely worth less now.
I since bought a 2014 Synapse Carbon which I love.
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