The problem is neither of us are clear on it either.
She brought the car in after over heating.
They told her it was undrivable and would cost thousands to fix and not worth fixing.
[I can verify the above because they told me the same thing about the car. I used to use the same mechanic until this happened.]
So she left it for a couple of weeks while she considered what to do with it. Pay the thousands? Scrap? or sell for parts? She didn't think this was a problem as no one from the garage contacted her about it and as she had a good relationship with them and had given them plenty of business in the past.
During that time, she saw the mechanic driving around it in. How could he be driving around in a car that was undrivable? He either lied about it being undriveable or he went ahead and fixed it without her consenting to it or to the costs.
When she went to confront him about it he refused to release the car until she paid for the costs of the repairs, which she did not agree to him doing.
She went to the local guards and they told her this was a civil matter.