Secure A PHP Page

Attached is a PDF of a php file. If you look at the file you will see that a cross site scripting vulnerabilities involving ($_GET['dir']) and ($_GET['sub_dir']) have been fixed by another coder but we KNOW other vulnerabilities exist.

Please review the attached file and advise:
1. What vulnerabilities exist
2. Your price to complete the work.

Please DO NOT waste my time by telling me how good you are. Just quote a price and advise what you intend to fix to make the page 100% secure.

Please note that the deadline for completion is Friday 19th November at 12 noon GMT

Thank you