I'm developing a new line of web-based videos and this will be my first time pitching a series to potential sponsors. My thought is to run 2-3 second preroll ads displaying the series title, brought to you by company's name and logo. I'm told rates are usually determined per view, for example 3 cents per impression. I will have a spec example online and I can compare the number of views it gets with similar established series, but given that online videos will accumulate views indefinitely, I don't know where to cap it. For example, if I ask for 3 cents per impression and tell them they can expect at least 10k views in the first 6 months, they throw me $300 for the video. What happens when it accumulates the next, say 5k views? How would you recommend structuring an agreement?