What do I need to do before launching my web-based business?

I'm developing a customer review and social networking website for a niche market. I'm not familiar with website development but I have someone lined up to do the work. However, I need to create a requirements agreement prior to him beginning...and I don't know what should go into the document or how it should be formatted etc. I also need to sell advertising space on the site but don't know how much to ask (per month, annually). I've heard that allowing companies to bid on advertising space is a good alternative. Any information on these issues or additional pointers would be GREATLY appreciated!! Thank you!

functional requirements: basically you have to describe the functionality of your website the way you see it. the best way to do it to copy/paste screenshots with some functionalities from other websites and say 'i want this'

adsense is the name of the program that allows you to add advertsing on your website -- they take care of what ads will be delivered on your website. anyways, without having over 1mln pageviews per month it makes no sense to directly search advertisers on your own, leave adsense to do the job for you.

would you mind PM your MSN to me? thanks.
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