What's a new iPhone 4S worth?

I want to know what's the most a four-month-old factory-unlocked iPhone 4S with 8GB is worth if it comes with all the original packaging and documents verifying authenticity of purchase. It's in excellent condition both in and out.

Sure its good but suggest to check the price of new iPhone 4S in market and online as the festival seasons are going you can find best deal online too with offers and discount.It's worth if you get all the original documents and iPhone is unlocked too.