Bidding portal/website

This is to get quotes and estimate whether project funding is sufficient or need to find more funding. These User Requirements (attached) have been written for getting quotes for the development and hosting of a portal/website where customers can place assignments and individuals and companies can bid on these assignments. Examples for this could be a site for construction work. PLEASE refer to the detailed specification BEFORE giving the quote as budget will be fixed and increase will not be an option.