Hi Alberto, this is Bill Ballard, owner of Bonita Valley Auto Care. I have spoken with my service advisor and even though he discounted the repair order for the additional service needed, the cost for the service never should exceed the original estimate. I don't like to add any surprises to our customers who trust us to repair their vehicles. Email me at email@example.com and I will set up your refund to the original estimate of $740. Also I would like to offer you $20 in gas for the inconvenience.