Someone recently asked me this question: How many products (ebooks in my case) do you estimate you will sell per month? I replied that I didn't know and will have to wait and see. They told me I had not done adequate research on this and in order to find the answer I would need to know my competitors conversion rates, what sales channel(s) work best (such as affiliate sales or direct site sales etc.) and the average amount earned by people in this niche. How am I supposed to do this, it's not like I can ask a competitor those questions and I certainly don't know where to source it? Can anyone give me an answer on how to do this, really appreciate feedback.