Most 'professional' dog trainers don't get hard working dogs, especially hard Dobermanns, so you have to be careful you don't get someone who permanently fouls up your dog. And 'normal family training' (what's that anyway?) won't cut it either. A good breeder will provide you with the necessary info and direction (e.g. socialization, building drive/focus, do's and don'ts, etc.) to train your working dog. It's not at all that difficult, one does not have to be 'an expert', it simply takes time and effort on the front end.