1 Quarter horses are also used for rodeo/barrel racing or working cattle, along with Arabians and Thoroughbreds. 2  These trained animals average $2,500-$7,000, but exceptional animals cost a great deal more.3  English jumping riders chose Thoroughbreds and other breeds which can start under $2,000 but often run $3,500-$8,000.weet. Comments (7). The price of horses varies according to what they will be used for--Trail Riding, Rodeo/barrel racing or English jumping--and how much training the animal has. The basic rule of thumb is the more training and experience a horse has, the more it will cost.