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CL/Facebook, Amazon (seller account), Swappa in that order. I usually try local first to get the most money. Then Amazon seller account because it actually is usually less fees than Swappa (when you take Paypal fees into consideration) and usually sells much quicker than Swappa.
 
Craigslist is your a seasoned seller. It's top dollar. I just ignore all the scams. Does take some time to learn how to post and how to interact with potential buyers.
 
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