We never used a trainer with any of our dogs. One of our dogs was reasonably well-behaved anyway. The worst thing she tended to do was eat rubbish (such as discarded food) on the street. Apart from that, she never really did anything exceptional. She was basically a very gentle, caring dog so we had no reason to get a trainer for her. One of our dogs probably needed training but we never did it. For one thing we had no money for such an enterprise. For another, I am not sure it would have helped much. Although she did not listen at all, I think it was more because she had such a small attention span and could be so easily distracted or frightened by loud noises. Even if she were trying to do something, if she heard a loud noise in the distance, it would confuse her and she would run off to either hide from it or investigate it. She did have aggression issues too but we always kept her on a leash when we took her for walks. Because of her excitability, she would probably not have been able to find her way back to us if she ran off.