I have an xbox one and I want to sell it to buy a PS4.For how much should I sell it?

It has two controllers
With 7 games.
1.Grand Theft Auto 5
2.Call of Duty Advance Warfare
3.Farcry 4
4.Halo The Master Chief Collection
5.Mortal Kombat X
6.Minecraft
7.Battleblock Theater

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