Animal Care Needed - Full-time / Part-time

We have a 50 lb Sheltie named Chester. He has gone to a couple of groomers in the past. Unfortunately not on a regular basis so cciat was thick and matted. Last groomer shaved him. He has grown out again and is looking shabby. We are in our late 60's and too much to keep up with. He is a kind and friendly dog. Spoiled rotten. He doesn't bite unless you are grooming and pulling hair. He will probably need a muzzle for that. Otherwise bathing and nail clipping goes well.