Hello Gimmethebag, shiba and scarlet555 : thank you for you all great inputs and information.
When I saw it in person and compare it with my Lazare Kaplan diamond with Ideal cut , p & s are excellent, F color VVS1 that ring look really good and sparkle a lots, color is white and shine.
Seller asking for $4000. Is that fair price? We are not decide yet until tomorrow.
We did search a lots from eBay and some websites, range of that ring over $5500. Some of them don't have Cert or boxes.