I have been charged 5 hours labor @$85 per hour by Auto Therapy of Gaithersburg to replace the Water pump, thermostat and hose on my 91 735il. I had planned to do it myself but due to other pressing issues I had to take it to this independent German car service facility. The owner Roger Bratter claims to be a specialist in Porsche performance but I find it unusual that it took him 5 hours to replace the water pump. I could have done it in 2 hours max! Does anyone have any experience with Auto Therapy? Did I get ripped off?1991 735iL