I came in due to my stabitrak light was jumping on...

I came in due to my stabitrak light was jumping on. The young man explained to me that I still had some warranty left and would be covered or worked in. He had me to sign a paper to find out what was going on. Never did he say, if it is not covered it would be a charged of $118. When he came to tell me what was wrong, he said that the sensor was not covered and it would cost $418 to repair. I explained to him that I would have to speak with my husband before getting any work done for that amount of money (we are on a budget). When he came back with the paperwork, still at that time he did not say anything about the $118. The cashier said it was $118 and she called him back in which he said that it was explained to me. If I knew it was going to be $118 before starting anything, I would have told him that I needed to come back at another time. He then said that if i would have fixed it that day, it would have been included in the price. I asked him if I was to bring it back would that $118 be subtracted in which he said no cause his guys have to get paid for finding the problem today. I'm pretty sure, the computer read the codes which wasn't $118. The paper that I originally signed I'm pretty sure it did not say that I had to pay $118 if it wasn't covered. Hopefully this is not how you guys make your money.