Correction, OP will not get many messages from legitimate SEO providers. He will get tons of messages from overseas link spammers that will "get you first page of the googles" and take his money. These are the same guys that would have done the exact same work for $250 per month or even $99. As for asking for margins that is a big load of crap and I have never heard of anyone but the government asking for that in a request for proposal. Then to tell some noob the exact methods used so they can replicate and replace (you) would be just plain stupid. With all respect to OP this is a quick way to attract all the wrong partners. You are about to be flooded with proposals from India and PI all guaranteeing they will get you to the first page and all claiming to be "SEO expert." Good luck, b/c these guys may know how to run SEO apps, they can not write anything worth posting to save their lives and they think social networking is about spamming friend requests from fake accounts.