Variations in estimates happen for several reasons. Anything that is a considered a repair on the damaged vehicle is a judgment call from the eye of the person looking at the vehicle. The choice of parts used make a big difference. Some collision centers will write for used or aftermarket parts without being told to by the insurance companies. Others may use OEM Genuine parts or aftermarket parts per your request. Additional reasons stem from the expenses inquired from the equipment used and state of the art facilities. But one of the major reasons estimates vary is due to how the estimating systems focus on different variables, including how the cost of labor is handled. It is important to recognize that additional items/repairs are frequently needed to repair the vehicle properly. It is the shops obligation to make certain that all necessary repairs are completed properly regardless of the initial estimate.