Replacing factory installed radio with another
 

I have a Kia Sedona 2009
The factory radio that I have has only satellite and not Bluetooth.
I was hoping to call around to a wrecking yard and get a replacement radio that has Bluetooth
First how do I find out what factory installed radios will fit in my car
Second I went to the dealer and asked about a replacement radio with Bluetooth he told me that If I went that way there would be alot more wiring to do than if I got an after market product. I cant see what extra wiring would have to be done only thing I can think of is maybe a mic
Any thoughts on the mater