What education and/or training do you have that relates to your work?
I hold an international credential that of Certified Professional Dog Trainer-Knowledge Assessed. I have to earn 36 continuing educational credits in a three year period to stay certified through the Certification Council of Professional Dog Trainers.
What types of customers have you worked with?
The Coaching Package is by far the most popular service I have. I work with you to teach you management solutions and training skills so that you learn how to work and build a bond with your dog. Training happens between the scheduled 'lesson' times. You are ultimately responsible for your dog's behavior. You get what you put in. You will also learn about a dog's learning patters, learning phases and schedules of reinforcement that help establish desired behavior and maintain strong responses.
What advice would you give a customer looking to hire a provider in your area of work?
Dog trainers are not all alike. It's a craft ~ profession and not one that is regulated. You have a wide extreme of philosophies, skill sets, coaching abilities, ethical issues, behavioral sciences or lack thereof and anyone can call themselves a Dog Trainer or Behaviorist.
Look for someone that has credentials and that continues their education to maintain their certification. Ask about what equipment they use and why. Observe a class before paying someone.
Here are three good links to read: http://www.apdt.com/petowners/choose/
Be careful who you trust with your dog's behavior and education.