No problem at all, but thank you all for sharing your opinion.
My ex-D750 is from grey market and I lost only 2% resale after 1.5 years :D. Maybe you don't believe, but it is true. Lucky me to sell it on the D850's official release date =)).
Sometimes I ask myself why taking risk buying used camera instead of keeping it, but my camera is like without warranty, so same for buying a used one. With many recalls of model, who would take risk to buy it as my serial is listed :(.
However, with experience gain, we may be able to detect flaws from used camera and get a good used one, maybe :).
Finally, I decided to hold my heart down a few weeks more waiting for price drop of new or used D810 .