Car hire problems & poor resolution procedure

I booked a holiday in Sicily - flights, hotel & car hire. Flights and hotel were fine. But the car hire was a real problem. We paid for hire and CDW up front but when we got to the airport in Sicily they insisted we had only basic hire - no CDW and minimal cover in case of accidents (far short of AA type cover). We ended up paying over £140 extra for CDW and Roadside Assistance for a week. Travel Republic forwarded our complaint and got a list of charges from the car hire company ("Jigsaw" acting as an intermediary for Budget) that were all new to me, including ones that were supposedly included in the original hire charge, such as airport fee. These were clearly created retrospectively to cover the charges that were actually unjustified. Travel Republic offered no help. The simply passed on the message that we had signed an agreement so that was it. They refunded £35, but showed no interest in pursuing the problem and simply stated firmly that I could go to ABTA if I am unhappy.
They deal with intermediaries and accept no responsibility. I will not use them again, and will never book car hire through an intermediary again. I'm very disappointed in them. Trailfinders are far better, or else just create your own package.