I don't need to know how the sausage is made, I just need to know how much does it cost. If I'm given a fixed all included price upfront, I don't care how much

I don't need to know how the sausage is made, I just need to know how much does it cost. If I'm given a fixed all included price upfront, I don't care how much of if goes where inside of ISP. Now, if they quote me one price and bill another - then we have a problem.