This horse is a nice little package. She has a strong topline and someone has done some correct work with her. If she was correct running barrels (able to collect and extend solidly) then that is where it comes from.
Somethings to notice on this horse:
In the photo with the rider, look at her neck. See the muscle that goes from her poll to just above the rein? That muscle has some start to development indicating this horse may be able to raise the root of her neck and use her ring of muscles to get off her forehand (as she would need to coming into a turn around barrels).
The only negative comments I have about this horse is that her shoulder is a bit steep and her point of shoulder lays a bit low. Her hocks have some set to them and she is a bit camped under. She has a longish coupling but because the ring of muscles has been developed, it is very strong.
I like this horse a good bit.
In the photo of her standing looking at her left side (the first photo) look again at her neck immediately next to her eye. See that little bulge? That is the start of nice muscling indicating she is part way there using her ring of muscles.