^^ my thoughts exactly, the one person who did guess a breed was assured that this horse was a thoroughbred. as for her height, she looks to be in the 15.2 - 16hh range.
Anyway, I can't add anything conformation wise, she looks like a decent horse, I wouldn't say I LOVE her, she's not really my type personally. she would be a decent eventing horse, I see no reason why she wouldn't be, unless she didn't enjoy jumping or dressage. If you do think about buying her, get her vet checked, and make sure you, a trainer, or the owner riders her.