I could probably go on and on about the benefits of hiring a personal trainer and what kind of "value" you get for a monetary exchange. However, this article does a great job at pointing out six really great reasons.
1. Trainers provide accountability and motivation
2. Trainers provide expertise
3. A trainer will push you just enough
4. A trainer helps you identify and reach goals
5. A trainer will personalize your workout
6. Trainers can reduce the possibility of injury