I need a Drupal developer and themer, who knows about Drupal security

General information for the website: We are a European Organisation
Kind of development: Customization of existing website
Description of requirements/features: Please - UK based freelancers only -

We have discovered some spam links on our Drupal 6.28 website. We would like to:

1- Rebuild the site using the latest version of Drupal
2- Transfer over the old content, making sure nothing has been injected
3- Set up automatic Drupal updates
4- Conduct a review of the current user accounts, forcing a password change and strong passwords
5- Additionally, we would like to update the theme of the website to make it mobile responsive

Please provide with with individual time estimates for 1-4 above, along with your hourly rate. I can then show you the website, and you can provide a quote for 5.
Extra notes: Ideal candidate will have general knowledge of coding PHP (such as regexes) and linux server administration