One, horses are started at different ages depending on the breed/build/discipline. Lot's of people disagree with the way things are done.
Next, as far as training go's, remember, it's a baby, it's had 2 months of training. Don't get mad if she doesnt do everything perfectly. Picking up a canter with a rider on the back in a round pen is quite a feet for an unbalanced horse! You have to remember she's learning to carry a rider on her back, she probably would have picked up the canter on a strait of way in a larger area. She's just a baby... You can't expect collection and perfection from a little one.
Also, as far as the spurs go, the latest thing with QH's is to "spur break" the horse, You need to ask what the trainer tought this horse becuase if it's spur broke, then you are looking at a completely different way of riding, the spurs are actually used to slow the horse down and stop her.
If she just used the spurs to make her go, then in all honosty, you can change the way a horse responds to you. Any time you get on someone elses horse it takes a while for you to learn their buttons and for them to learn your commands. You can get her to respond w/out spurs if you don't want to ride with spurs. I think she's worth another look, just don't make any quick decisions.
And as far as QH's go, they start them at 2 for the AQHA circuit. You can wait until 3 or even 4 if you want to. I would not suggest jumping before 5 (but that's me)....
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