When looking at unfamiliar horses, whether as training prospects or to purchase for a client, I have a very specific mental check list I go through:
First, I like to see a horse in his stall (if possible) and also observe how he reacts to people around him. I particularly want to watch him being groomed, saddled and just handled. I would like to see a horse that is ready for work, likes his handlers and is just A-okay with everything around him. In other words: not worried or anxious, nervous or angry.
Next, I like to see a horse lounged. This gives me an idea of overall soundness as well as an insight into his personality. Is he quiet but playful? A big plus as I really like playful horses. Is he well mannered, not charging around but waiting patiently until his handler is ready to start. Does he exhibit a frenzy of energy (not a plus, but definitely okay). I must add that I like energy and I'm not fond of lazy horses since they can become sullen. I will question though whether the energy level of the horse matches the work the horse will be asked to perform.
Personally, I really like to watch the horse's owner or trainer ride him. This gives me a more accurate idea of what the horse "knows" and what he can do. Also, I can see if I like the way the horse looks under saddle, the way he carries himself and see more of his general demeanor.
Last, I will ride this prospect myself. I like to just gently flex the horse around and see how he feels in my hands and how he reacts to me. I'll move him off my legs, make him bend and turn this way and that. I'll then go through his gaits one by one, all the while observing his reactions to me. Is he cross or unsure, or is he willing and confident? I really like to gently prod him with my spurs and just, in general, try to find out if he's tolerant to being trained and asked to do things that may be slightly different (just slightly at this point). I do all this slowly and in a manner that should be easy for him to accept. See you next week, JD.