Wow I am sorry to hear about the problems with your neighbour... My boss runs his business out of his house as well but none of his neighbours complain as my boss owns the house on each side of him and basically got to " choose" his neighbours.... Yard backs onto a railway line with a tall fence so no one behind can see in to where the shop and parking "lot" is...
Sounds like you have one of them neighbours that likes to whine and squak about everything... just a PITA if you ask me..
A.D
