Site hacked OR file uploadez on my website.

Hi all My website www.*****.**have been hacked. actually I think it has been hacked. Some file appeared in the FTP side and a directory. Some .dat files containing a list of websites and emails. I guess it is just a matter of "failure in my Js code or Php code. Bidders are required to have a look the site carefully and resolve the problem permanently. I will pick a free lancer already having experience with such hacking bug fixes The freelancers will have to explain what he did and what was the issue. Low budget is welcome When awarded the project to a freelancer, I will provide a ftp code for him to work. Please let me know your COST and TIMELINE for this job. What all will be required from my side to make this job done. NO MILESTONE, PAID WHEN DONE. Please have a look at my profile, I am hones, effective, precise and pay fast. Thanks