Salmo, are you a (big) dog person? I think a good size Rott would solve the problem. It sucks to have to worry about you're neighbors. These kind of people you have to make an impression that you won't tolerate any BS ! Good luck !
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He who joyfully marches in rank and file has already earned my contempt. He has been given a large brain by mistake, since for him the spinal cord would suffice.

- Albert Einstein.