I understand your frustration. This is a training issue, so you'll need to start with specific training before you groom again. I'm not sure why you were charged so much for their handling time, unless they did accommplish the bath, nail trim and some brush out?? Reccommend making this a weekend project. Start by using your hands, skip the slicker brush for now. He needs to understand "stand" , "stay" and "leave it", your biggest problem being that he's lacking the obedience training to distinguish this from playtime right now. Then when you add things that may be a little uncomfortable, (metal brushes) it becomes frantic or aggitated behavior. Try having someone in family hold his lead, while he's standing in the livingroom on carpet. (No slick tile surfaces) His collar will be tightened a little, just under jaw. The human post stands in front of him. You're to give command "stand" while you're off of his right shoulder. Gently take his collar in your right hand and use your left hand to place it on his "knee" while applying gentle pressure to move him back. He may already be standing, so you're simply getting him to shift his leg back. There just has to be movement. Then quietly reward with something like chicken! He's rewarded only while he's still in a "stand". You're then going around to the other side and repeating this exercise. All your teaching him is that when you are close to his body and touching his legs, he's not to swing around, not to use his mouth and not to jump foward. The 2nd handler stops the foward motion. The second he's quietly shifting only the leg when he feels pressure, without resistance to you being back there, you're then going to lift the leg from the knee and start running hands down leg to paws. You'll do this on his back end for first day. Second day start this exercise on the front end. Your commands are very quiet, very calm and you keep quietly repositioning him if he shifts. The person holding the lead is simply a post and does not speak or correct dog. They're needed to keep him from swinging around and grabbing at your clothes or hands. Next, work on adding running hands down leg and picking up leg, then going down to paws applying even massage/pressure. He's being well rewarded and baited thruout this exercise. When you hear that big sigh from him, and see he's settled into a standing position and relaxed during this handling, you're ready to move onto going over his back. Gentle massaging pressure from the shoulders down the back to tail, while he's required to "stand". If you were commited to doing this exercise for 20 minutes per day over the course of two days, making it a pleasant experience for the dog while also convincing him this is not playtime, you're not asking him if he wants to be handled... you are going to handle him, you are going to be persistant, but there will never be any pain involved, then by mid week, you should be able to move onto using the brush again. By next weekend, you should be moving onto using the brush, getting your dog to "stand" and stay without assistance from a second handler. This is simply a desensitization exercise and a matter of "manners" when he's being handled. No firm correction or a lot of fussing around, no head restraint, tieing him up, ect. He really needs to "get this" and find it pleasant at the same time. Good luck!