Already designed Websites to choose from

Hi guys, I am looking to setup a platform where I would allow my members to select from different categories of already designed websites and then they would just do a little editing such as they would add their own Logo/header at some points where would have marked that they could add their logo to. then they can type in their content on pages like : homepage, about us,services/products, contact us, Now basically, the idea is that I wanna offer people offline the opportunity to own their own websites by choosing from what we already have and they would just change the colours or whatever need be changed. Websites categories would cover different kind of offline businesses that people have such as : Fashion designers, Restaurants, Automobile guys, Mechanics, Real Estate, Home school teachers, Lawyers, Consultants, Pastors of Churches, Private Schools for kids etc. Point is each category of website would reflect that business or profession. If say a Fashion designer for instance, then it means the website would be built with several angles for several pictures or images , different angles for flash images to be uploaded once they have theirs. So basically, the owners even without prior IT knowledge or skills could easily just replace or upload and then save. Now the second part to this is that we are looking at a situation whereby they can immediately SAVE their edited jobs and it automatically is hosted online and they can view with certain URL and ofwhich much later they can very easily purchase their own domain from Godaddy or any other and then they would point it to our Subdomain or URL which they already got. .... Also, it might be a good idea that after they have selected and edited the website to their feel and look and want, they would easily yank it off and host it elsewhere that they prefer. I am not sure how this can work best. But I do hope that you guys can figure out much better what I want. I need an urgent quotes and pls be very realistic. We would also need this job completed the fastest time possible. We already have our major website and backoffice so, we would need for this to be transferred or integrated into our members only backoffice from where they can access these with their passwords and usernames that we have provided for them. Thank you very much.