Convert website from Joomla to Wordpress

I have an existing website ([login to view URL]) built in joomla which I want to converted to wordpress. You may suggest to me a suitable wordpress theme (free or premium) and I will evaluate which is suitable. The main work is the ask question module which is the key feature of the site. The rest of the plugins can be handled by me. Even the directory, i can just get a suitable plugin to fit into the wordpress theme. It's a typical stackoverflow (question and answer) site for user to post questions and merchants to post answers. Admin will be the moderator to approve/reject the questions. If you feel that it's easier to use an existing question & answer wordpress themes/plugins to work on this, please suggest them to me. I am looking at a budget of $200 for this project, please bid only if you can work around my budget. Below are the requirements for this site: Ask A Question a. Users can post question and merchants can post answers – refer to ([login to view URL]) for sample b. User need to input their display name, category, email address and the question. (May need to register) Yes will need them to register upon posting questions c. All questions posted will be reviewed before publishing. d. Merchants will receive email notification whenever there’s a new question posted e. There will be a ‘Reply’ link for merchants to provide answer. User who posted the question can also be able to reply back to merchant’s answer. (see Propertyguru for sample) f. The set of questions/answers displayed in the homepage is based on the latest entries. g. There will be two tabs (Latest Answers & Most Popular) – refer to Propertyguru for sample h. Most Popular simply refer to the question with the most answers given. i. All questions will be categorized and the categories can be managed from admin panel Public Users able to do the following: a. Dashboard to edit profile information, change password, etc.. b. Post questions in Ask A Question (Submit to admin for approval before publishing) c. Able to see a history of all past questions asked d. Able to reply to answers (Only to the question they posted) Merchants (IDs/Contractors) able to do the following: a. Dashboard to edit profile information, change password, etc.. b. Display the list of questions posted by users (Question will be marked as Answered, Unanswered) c. Post answers to question raised by users d. Able to see a history of all past answers Admin able to do the following: a. Approve merchants’ registration b. Add/Delete/Suspend merchants and users c. Manage Questions/Answers - Approve/Reject new questions (Reject with reasons) - Remove or hide posted questions/answers d. Add/Edit/Delete categories of questions