F & S Plumbing

I called my builder Eastwood that the house they build about two and half years ago leaks on the garage ceiling. I was told by my home builder that I need to use F & S plumbing company to keep my warranty but I still am required to pay the plumber any fee associated to fix it.. not sure why my builder insisted to use them yet they don't pay for it... anyway, I used this company anyway thinking that they would know the design of the house and where the joint for the leakage comes from. The guy came in and I told him that I think the washer upstairs might be the where the leak comes from. He just told me to put the rubber bolt underneath the pan but I have it the other way around. After he spent 5 min for this, he called his boss to check if I need to pay since he did not do anything and only spent less 5 min in my house... And came back and said his boss said I have to pay $100... This is too much for less than 5 stay... Never want to use them again.