If you have the opportunity to go and try the horse, then do so. A short visit to Europe is much cheaper than having the wrong horse shipped across the ocean, and there is no real alternative to feeling an animal under you. When you go, stick to the correct sequence rather than just jumping on.
Start by looking at the horse in the stable and touching it on the ground. Run your hands down its legs, observe it walking and trotting on a hard surface, and note its behaviour when it’s been put on its tack. Then have the seller’s own rider ride the horse in front of you; this is not optional, and a reliable seller will expect it. It ensures your safety when dealing with a horse you don’t know well and allows you to see the horse’s true first minutes as well as what it can be like when ridden by an experienced rider before you get on.
Take the horse yourself and plan a session. Begin by walking on a long rein, then go on to work through all three gaits and carry out a good number of transitions on both reins, and ask the horse for the movements it was meant to know. Along the way, make a deliberate small error and observe how the horse reacts. With any horse that you are serious about, return and ride it again on a different day, since the first ride gives only a first impression while the second provides actual information. The test of trust is ultimately simple: do you want to get back on tomorrow? If the honest answer is a polite “it was fine”, then keep looking.
It’s not possible for everybody to make a trip to Europe at short notice, and for buyers in the Gulf, in China, in India or in the far part of the United States, taking a trial ride is a major commitment. That’s why a proxy rider is needed. A professional who is independent and who understands your style of riding should go, take care of and ride the horse, enabling you to get a proper feel for its temperament something that a video never can, so that you’re making your purchase based on real information rather than on hope. This is one of the services we provide for this very reason, and even if you organise it somewhere else, you must insist on having in writing details about who the rider reports to and who is paying them. An opinion the loyalties of which you can’t check is no better than advertising.