1. I would suggest getting a trainer that focuses more on positive reinforcement than negative. Positive reinforcements TEACHES a dog instead of using fear or consequences.
Example: Yanking on a leash in order to get your dog's attention - doesn't really teach your dog anything other than to not have as much of an enjoyable walk because they are too focused on making sure that they are not going to do whatever it was that made their handler yank on the leash. It tends to take longer for them to learn what it is you are asking for so it isn't necessarily training that the handler is doing.
A trainer that uses positive reinforcement may use treats and praise instead to grab their pet's attention and give them such items when they do what is requested at the exact moment therefore it creates a learning experience.
2. You should look for a trainer or behaviorist that is also great with people. This is because they are training YOU as well. You have to learn everything and pass it along to your pet on a regular basis. If the trainer is condescending, indifferent to your presence or just plain rude then you as the take over trainer are not going to feel comfortable and are not going to soak in as much information.
3. Be wary of "Too good to be true" tactics. Training your pet is an ongoing process. While your trainer may be able to teach you the tools to the trade if they are more focused on getting you to sign up by offering gimmicks or sales pitches then it may not work out. Some clients have found that individuals who offer gimmicks or sales pitches such as, "If I can't do it, then no one can!" or "Specializing in military canine training" or "Training done in one session or your money back" tends to offer more of a quick fix approach. Your pet is most likely not military or police and needs to be treated as a member of the family instead of a working canine.
When your pet is actually learning what you are asking instead of just reacting to certain stimuli and tone it is a beautiful thing to see.
Let me know who you like in the area! I personally have found Dawgma Animal Services to be top notch and go above and beyond. They have helped a few of my clients who had nothing but good things to say.
What has your experience been like with local area trainers/behaviorists?