go to a diff toyota garage and say nothing about the other garage and say you were driving up a hill then all of a sudden the car started to rev......make out you drive it more....tbh their is an old woman comes in to my work in 6000 miles shes had 3 clutches shes not had to pay for one yet!! but you cant really blame the car if your mum slips the clutch too much.... but try what i said and see how you get on but you must try an other dealer.....