I bought a NX1000 off eBay used about 8 months ago and haven't had any issues with it. A few days ago I went out with my friends, shot some pictures and came home. Tonight I tried to power on the camera but it wouldn't turn on and no light on the back would come on either. I've tried 3 fully charged batteries: removing them, leaving it without a battery for a while, and just about everything you can imagine, but it just won't turn on and no green light lights up on the back. Any help would be greatly appreciated.
Did you try a factory reset ? Normally there is a way ( described in manual ) to completely reset a camera to out-of-the-box settings.
Have you tried to start it without a lens, in case the lens ( or mount ) is an issue ?
Did you at any point try to upgrade the firmware, as an incomplete firmware upgrade would "brick" the device.
Check the battery compartment for dirty connections or similar.
Take out the memory card while trying some of those things as well. Just in case.
That's about all I can think of off-hand.
As you had it for 8 months since purchase without problems, it cannot reasonably be related to the seller.
I have been trying to fix my NX300 for over a year with this same issue.I talked to several support people at Samsung and didn't get a resolution, and was getting very frustrated.
Finally, Joshua at Samsung walked me thru a firmware/bodyware update which was NOT easy to do, but fixed the problem.
You have to first install the update to your camera, but then you have to open that update from the camera device and UPDATE from that point - both the firmware and bodyware. The bodyware update was the one that fixed the issue. And you must select that as the update, the camera will not find it automatically!