I just upgraded the radio on my and my RV. The car had a double din, and I put a pioneer unit with a touch screen that will do pandora, spotify, dvd/cd, bluetooth, hands free calling. I added a back up camera and could add satellite but didn't.
For the RV I got a single din unit (that is what the old unit was), real simple no cd player but does have blue tooth and a mic for hands free calling.
I spent about $300 on the car and less than 100 on the RV. Basically you can find wath you are looking for pretty easy. I did use Crutchfield and called their tech support a couple times as there were some set up issues that weren't well explained it the instructions, they are great to work with.