I am trying to figure out how to use the placements option and have the highest ad for the cheapest cost. How does placements work!
You select websites that you want your ads to be shown on, while using content bids. So it is best to find the most relevant websites (or even competitors if they are using adsense) and using these URL's as placements.
Good Placements in the Content Network are essential for a successful Content Network Campaign. I like to let my ads run for a while and view my placement report frequently. This will help you find the sites that truly convert for you and weed out unwanted placements.