I think you and your dog would do better with a behaviorist in stead of a trainer. You said your dog can sit/stay/no. Her issues are with her behavior not her training.
Talk with your vet and ask for a reference (behaviorist) and then ask the behaviorist for references if you'd like...if you are short on time, meet the behaviorist your vet recommeded and go with your gut feeling.
Cesar Millan is a behavioral expert and he trains people. He is not a dog trainer.
Hope this helps and I wish you the best. Peis are tenacious, as you know. I prefer the word tenacious. Stubborn is a human characteristic not a good word to discribe a dog. Dogs are not human, they are dogs
If you are going to spend your money for private time, get your monies worth with a behaviorist. You will get to the bottom of the issues and work with you dog instead of against her.