How much should i sell my Nikon d40 for? - 1

I bought my camera i few years ago, and now i want to upgrade. It is in great condition, clean the lens and it would look brand new.

i bought it for $612

i also have two batteries, charger, 18mm-55mm lens and two memory cards

Added (1). I'm saving up for a Nikon d3100 actually, I'm very close. And a friend from school asked if he could buy my camera from me if i didn't want it.

originally i was going to keep both, but when he asked me about it i thought, why not sell my d40?

$300 on ebay or see if your local camera store will trade it for credit for a new camera like the wonderful Nikon D3100

When I want to know how much something is worth, I look at the completed listings on ebay. Not the currently listings. That is what the other responded did, and found the $550 amount.
Course, there were others that sold $300 or less. When I sell equipment I usually price it for the going price, but take less if the person wants to bargain cuz I won't have to pay the ebay fees if I sell it locally.