Frontier Frontier Communications The Company told me instalation was free and later I get a $494.95 bill and they won't take it off. Rochester, NY Nationwide

I called for internet and phone service frontier salesman told me free instalation and my bill will be $49.95 a month.  I said great I made an appointment for them to come out.  The tech came out and i told them the salesman told me free instalation he said usually it is expensive to instal let me make sure its free before i do the work.  I said ok sounds good.  A while later he says your all set i'm going to start working on it now.  He finishes the work and i said thank you.  Two months later I get a bill for $494.99.  I spent hours on the phone trying to fix it and they tell me there is nothing i can do i have to pay it.  So they did the work fraudently changed me.  Told me the work was 100 percent free and give me a bill to pay for 494.90 and tell me there isn't anything i can do about it. So mad, i am not paying that bill.