Build a Website

Hi, I want to build a website that allows Interpreters to register as a service provider (interpreter) and Interpreter seekers (client) to view interpreter profiles and contact them for their service. The function is basically: 1, Interpreter can register as an Interpreter and will be required to fill in their basic information like City, Rate, Experiences etc. and the information is searchable within the site using a search box that I want to put right on the home page at an obvious position. 2, Interpreter seekers(clients) can register as a buyer and post his requirement, which will be published on the bid list page that's shown not only on a page, but also at Interpreter's backend control panel. So I need a registration page where a visitor can actually choose the role to register. 3, A trust point system. Basically it's a way to suggest interpreters to post more experiences, verify certificates etc. to gain more points and the more points, the better ranking in the interpreter page/list.( Default sort criteria will be trust point descend) 4, Member ship levels. Divide into 3 levels, which will be different prices and of course, will be given more trust points which integrates with trust point system. 5, I would like to enable interpreters to post experiences, diary etc. and select some good one to show on a page. Posting will be given some trust points upon approval from admin. 6, I want the whole site to be a Responsible Minimalist site for SEO concern, that said, it doesn't have to(it can, of course) have big, fancy banners , BUT, it needs to look pretty also. 7, When a service provider adds his/her city, language, familiar industries etc. I want them to automatically be added to the left side bar menu as links so when visitor clicks the link, it goes to a page where all interpreters from that city, or speak that language or is familiar with that industry will be listed. 8, Enable admin to chance permissions of different roles (interpreter and client) on different pages. 9, I want a good user experience for service providers in terms of editing their info, display their info in a nice layout page etc. The filtering and displaying of interpreter info will be the most important function. 10, I know little about Open Source programs like Wordpress, Joomla, Drupal. I built a website with wordpress for myself by choosing a theme (which is not hard). But I don't know about coding or PHP etc. And for this site, I do want some flexibility in terms of adding/removing some functions if needed in the future by myself. 11, I have drew 4 important pages of the sites to help you understand it. BUT, I have a reference site for you afterwards, which will better explain it. 12, Duel to the fact that I don't have much budget on this site (but still I have so many requirements), I don't feel quite good for not being able to pay much on this site. But when the site runs well and I have income from the site, I will like to cooperate with you again on improving the site and recommend you to my other friends. 13, I might/might not have new ideas on this. I hope that will be negotiable afterwards. Thank you very much