Brake Disc Pads problems of the 2011 Jeep Cherokee

I purchased the above listed vehicle in April 2013, had to bring it back for an issue with the brakes. I had little to no pedal, brought the vehicle into the dealer waited approximately two weeks and the vehicle was returned to me. Service writer stated that being the truck was on the lot for a while, the brakes got warped. Was told that the brakes were changed. I left with the vehicle that had a little more pedal since I brought it into service. On or about the first week of Feb. 2014 I experienced my brake pedal was hard as a rock and I was unable to stop the vehicle. Brought my vehicle into service explained to them what was going on and they said it was the brake boosters. I get into my vehicle a few days later and once again I was not able to stop the vehicle, this time I almost was involved in an accident. I drove the vehicle almost 10 miles at 20 mph to the dealership and demanded they fix the brakes. The service manager came out got into my vehicle drove it down the street while I was the vehicle,the vehicle was there for almost five weeks, I finally received a call on April 10, 2014 that my vehicle was ready. I get into the vehicle I press on the brake pedal and the pedal goes right to the floor. I was advised by the service writer that I needed rear brakes and that is why its doing that. The cost for rear brakes was about 500. 00, I declined and told the service writer I had my brakes done several months ago and they should not be in need of repair. He looked into the system and told me only my front brakes were repaired, they just surfaced the rotors and put the same pads back on. I went to the show room asked for a 2011 grand Cherokee brought it to the service department and showed them a vehicle with 6000 more miles than mine and two millimeters less pad than mine and the brake pedal was full.