I've done it myself in accordance with VADIS. Its not a horrible job. Before you let a local shop do it, find out if they've ever done an S/V40 before. They ARE different. The transmission oil cooler is NOT incorporated into the radiator (its external). To access the ATF line to do the flush, you need to remove the battery and then the battery has to be replaced to do the flush (you have to start the car). Volvo has a very specific procedure you need to follow when you remove and replace the battery so you don't mess up the immobilizer. If your S/V40 is a 5sp, then you can't use plain old Dexron III, either. That's what the manual says, but Volvo issued a service bulletin requiring synthetic.