I am going to agree with ahearn.......are you sure Chance isn't too much for you? Please do not think I am trying to be mean or rude, I'm really not, I'm just concerned for your safey, Chance's safety and Chance's foundation.
From what I've read, Chance is lacking a good, proper foundation. Young, green horses are a serious, huge responsibility and if you don't know what you're doing (people in general) than you (again ppl in general) have no business handling a young, green horse. Young horses need you to be consistant and above all patient. Handling a young horse takes a great deal of feel, timing and savvy to deal with. It's a serious matter.
I do agree with the fact that you need to pick one kind of "method" to use on Chance and stick with it. Be it Parelli or not, if you do one thing one way and then the next time say "No, today I want it THIS way!" you will just confuse and frustrate her. Pick one and stick with it. SInce I do Parelli, if you choose that path I would urge you to contact an Instructor or go take a Level 1 clinic with an Instructor. Like I said, training a young horse isn't something to be taken lightly.
At the same time you are being consistant with your training, do not fall into the trap of becoming direct lined in your thinking. It sounds like that is what happened with you AND your trainer and Chance paid for it unfortunately. It's not about the task, be it ground work or riding, it's about building confidence, softness, and respect. Respect does not mean showing the horse who is boss, respect is showing leadership in the correct amount at the given time, being as soft as possible but as firm as necessary, trusting that she will respond but being ready to correct, but no one more than the other.