Website security, optimization, design and functionality examination and enhancement

Looking for a highly professional web developer/team to examine my current website (Khadamatonline dot net) before going public to undertake the following: 1. Examine the site server setting and the site files to ensure the utmost security and eliminate any vulnerability of any nature. 2. Optimize the site for SEO, including examining all scripts and modifying any necessary ones. 3. Enhance the site design, fonts and usability to achieve a user friendly browsing with clean modern look, including ensuring proper connection with the site’s payment gateways and social networks registration and login. 4. Enhance the site admin page design and functions to ensure full admin control over all aspects of the site. In addition, ensure full integration with the live site. 5. Dedicate a group of users to undertake all transactions on the site and use its features to test its functionality, and fix any problems that may arise. 6. Enhance the site responsive theme to ensure complete compatibility with all mobiles and tablets. PLEASE NOTE: A) Any cut and paste reply from bidders will be totally eliminated. Bidders should address the requirements above directly and show expertise in relation thereto precisely. B) 25% of the fee will be paid upon completing task 1 (security). Remaining amount will be paid full upon completion of all other required tasks. My profile and ratings by other freelancers should satisfy any concerns in this respect. C) Time is of the essence. This is an almost complete site. I’m not looking to develop a new site, rather enhance a current site. D) Please browse the site whose link is given above and evaluate it properly before bidding. E) Site in both Arabic and English. If you are unfamiliar with Arabic, you can work on the English pages, and I’ll do the Arabic pages provided a proper control is given through the admin site.