I was desperate to know how to keep raccoons away a few months ago just like you. But I eventually gave up and called a professional. The raccoon that terrorized us is a really big one, maybe 30 inches or so, and it raised all kinds of ruckus around the house. First it scattered the garbage, then dug the yard, and then tried to get into the house. I tried a few raccoon repellents to drive it away but all failed. In the end I just threw up my hand and called a pro to get the animal off our yard. Best decision, I would say.