After getting to know my sprinkler system, I seen it needed some work for sure. Lot's of broken heads or worn out heads. So I called a place that got good reviews, just to see what they would charge. After describing the system I have and the issues I had, she told me it would most likely cost $500! I said, thanks, but no thanks.
Today I stopped being lazy and went out to see what all the fuss is about. Dug out some heads/casings, unscrewed some heads, then went to Home Depot. Bought a total of 14 heads or so in two trips. Installed them, learned how to aim them and how to adjust the pressure. Now they work beautifully! My grass will no longer have odd yellow areas and I will no longer be shooting water where is does not belong.
So instead of paying $500, I spent about an afternoon and $50 to fix my own sprinklers. WIN! Not to mention I learned a new skill. Nothing to it really, but I got some experience.