Just today, I was engaged to get better results on Pay Per Click for a cleaning guy in California and here are some serious problems that I noticed in the campaign:
1) All Keywords were in Broad Match (OMG big waste of money):
Did you know that when you place "roof cleaning" in broad match, someone searching for "buy new roof" or "roof installation" etc. could end up clicking on your Ad. What a waste of money if you never installed roofs!!
So not just choose keywords correctly also select the correct match type (Broad/Broad Match Modifier/Phrase/Exact)