First off, my personal opinion is do not buy her, keep looking.
Multiple things that make me want to leave her and continue;
You had to wait a week for crappy pictures, they couldn't even put a lead on that (about to break) halter that doesn't fit.
She doesn't have a lot of muscle condition, and a poor topline. This really stands out to me on her for some reason. I'd bet money she has worms.
Her head, she has the ugliest, most unattractive head I have EVER seen on a horse, let alone a mare!
She is slightly sickle hocked, but severely underneath herself.
The owners are feeding their horses grain dumped right onto the ground.
I wouldn't waste my time looking at her.
On a positive side, I really love that shade of bay.