For your third requirement, rather than get a developer to develop an ad serving system (which can get pretty complex), you can simply use the years of experien

For your third requirement, rather than get a developer to develop an ad serving system (which can get pretty complex), you can simply use the years of experience built into this: http://www.openx.com/publisher/open-source-ad-server http://www.openx.com/publisher/open-source-ad-server -- it's open source and free (AFAIK) for you to use on your own servers.