Trying out a new horse

I'd be looking for safety first. You'll see at once whether the horse is the size (and possibly colour) and type you have in mind. This is what I personally would do:

* Ask about the horse's age (you can check teeth to verify this) and supposed previous driving experience.

* Ask the horse's name (everyday stable name) before approaching to introduce yourself to him.

* Handle the horse all over - head, shoulders, body, quarters, tail, feet. Both sides. Be wary of any areas of reluctance to accept you; odd shaped feet, lameness, unusual lumps, bumps, scars, or white patches from saddlery or harness - how were they acquired and do they have any impact on behaviour?

* If you're comfortable with the reactions, ask if you can harness the horse yourself while someone assists you by heading the horse. Is there any resistance to the collar being put on, crupper, breeching, saddle being girthed, bridle/bit? Note any oddities in the bit or the harness - why are they there?

* If you're comfortable with the reactions, ask to long-rein (ground drive) the horse rather than immediately putting to. Check what commands the horse should know and whether he responds as you expect when you use them.

* If you're comfortable with the reactions, ask to be allowed to put him to the carriage or cart, yourself, again while someone assists you by heading the horse. Be wary if there is any reluctance to stand still, or nervousness. The handler's reactions might also tell you quite a lot, body language rather than verbal is hard to fake!

* If you're comfortable with the reactions, go for a quiet drive - arena or trail will depend on your location but if you can do arena first then trail that would be ideal - with the handler/seller as your helper. Does the horse stand quietly while you mount the cart, wait till told to move off, and does he move off immediately you give the command? Does he walk actively and cheerfully, without wanting to rush into trot? Does he steer sensitively at a walk? Does he trot straight, without grabbing the bit or having to be pushed into trot? Does he go by traffic and scary objects without fussing? When you turn for home does he stay light in your hands, and not want to tear back to his stable? When you get back is he OK to pass the gate into the yard and obedient until you tell him he can go in?

Basically you're looking to go through a mini version of the steps you'd take to train to harness. A genuine seller should let you take as long as you want - you need to be happy with your potential purchase.

If you like what you've experienced so far, then it's down to whether you like the style of the horse and you "click" with each other. Some of that is gut feeling. You'll put up with odd quirks if you like the horse, and be endlessly irritated if you don't. A bit like partners really :) except partners can be expected to earn their keep whereas a horse just goes on eating!!