This will really depend on where you're located, there are places where you could maybe get $800, and other places where it would be around $3000, it will depend a lot on the market in your area
Longer backs are preferred by some of us depending on what sport you do. :)
As far as conformation is VERY correct. Her only flaw conformation wise is that she has a slightly longer back than preferred. Her hooves are in good condition. Great bone structure and muscle tone. She stays fat on air as well.
I agree with Deborah. With just that I would say anywhere from $1500 to $3000
Pricing depends on more than what you have listed. Confirmation, moving ,bonestructure, muscle tone , hocks, knees, slope of neck, length of back, hooves etc ... and thats not even my entire list of things to check, cause I am still drinking my first cup of coffee and a bit fuzzy just woke up brained still.