Nikon Camera Prices?

I want to upgrade from my nikon d3100 to a nikon d5100.
first, what is a reasonable price to sell my nikon d3100 for? I'm just selling the body.
second, what is the best price that I could buy a refurbished nikon d5100 at? Body only.
(also is it recommended to buy a refurbished camera or should i get a new one?)

If in the US, check for refurbished cameras at:
www.adorama.com
www.bhphotovideo.com
www.robertscamera.com
www.cameta.com
They all sell factory authorized refurbished cameras. The price and stock varies daily.
Also for Nikon, check the on-line camera store for refurbished cameras (www.nikonusa.com)
Whether or not you go new or used depends on you. Typically refurbished camera gear carries a 90 day warranty… But some retailers such as Roberts and Cameta often throw in an additional 3 to 6 months or more on the warranty (store warranty).
If you can get refurbished gear for a 25% or more discount, I would consider it (I have bought several refurbished lenses over the years). But if less than 20%, then I'd buy new for sure.

This isn't an upgrade - stick with your D3100 unless it's broken.

The best selling price can be 164 to 244 depends upon your use of old camera. Get new D5100 as it will have warranty with it.

Upgrading the D3100 to a D5100. Yes, it is a better camera, and here are some of the advantages of it.
http://snapsort.com/...ikon_D3100
And only you can say if the money is worth it.
Amazon has the used D3100 body for sale at $220. The condition of the body will vary the price.
http://www.amazon.com/...005PREXF6/
Since you can get a new body for $285, I don't know why anybody would buy a used one.
Looks like you could get a refurbished D5100 body for about $440.
http://www.amazon.com/...004V4IWHY/
I think refurbished is a great idea. If you can get the same camera for a $100 off, why not?

If you are going for a upgrade go for the D7100 or else stick with your D3100