90% of my keyboards have been sold here on Synthzone. Some on Craglist, and local paper. I used Ebay one time to sell a Kn7000.
I find that buyer and selling on Synthzone is a safe place to deal, but the price must be fare.

I have sent a check before I received what I was purchasing. My last sale I sent the keyboard before receiving the check.
BONUS: I did not just sell or buy, I made some nice friends. The list starts with Bernie and the latest is Jerry.

Life is good, John C.