Poor after sales service

I have been trying to get a quote for repairs to be done on my lounge suite purchased through Rochester which was already exchanged once already due to sagging seats, and i am being told that i have to take liability for payment of the quote even before i have seen how much it is going to cost me. The lady at the JD Group call centre (Zia) advised me that this is procedure but cant exactly explain the full reasoning behind this, she then said i can speak to the Rochester head Office, but their number just rings and no one answers.I am very dissatisfied with my experience with Rochester.