CT99RX300

My wife just took her 99 RX300 to get the brakes done and they told her that the caliper would not retract properly. This is in addition to new pads and rotor for over 1000.00 bucks!! Have anyone heard of these calipers going early. She only has 70K miles on it. How hard is it to replace the caliper and the rotors on this car? Is it easy to do yourself?