Keeping Dogs Away

Question
I constantly have problems with  my neighbor's
dog coming onto my porch lying and bringing odd
objects into my yard.  Although, I like dogs
myself and have spoken with the owners the dog
keeps coming to my porch rubbing on my walls
which make me have to clean constantly. Is there
anything I can spray or put down that will not
harm the dog; but make him stay away from my
porch?  

Answer
Yes, there are various dog repellents that come as spray, you can buy them from any pet shop. They do not harm the dog, however not all are very effective, unfortuneatly, you will have to try your luck untill you find a spray that is effective.
Good luck...