A discussion cum freelance website where freelancer can write articles and get hires.

I want a developer who can develop a discussion cum freelance website, the basic theme behind is that freelancers would be consultants or professionals, they will write articles on various topics of there own choices. The visitors will be allowed to read any topic they want, they can also ask a specific consultant about there queries and also they can hire that professional or consultant which would be there own sole arrangement. I have a domain [login to view URL], I bought this domain for the above mentioned purpose only. I want this website to be simple fast and elegant. I already have a bulletin subscription and we can use it here, if required. The website will basically run on Read, Write, Ask and Discuss behaviour, where users will be allowed to participate in any form they want. The developer has to make the website compatible on both mobile as well as desktop platform. Also I want all users to have a sub-domain based on there username like [login to view URL] which would lead to their profile or articles written by them. For this one can use wordpress also. I have no issues if you suggest only one pre-packed scripts or many scripts integrating together (like wordpress+vbulletin) which would be then modified for our purpose or some other alternative or a totally new script written from scratch.