491959 detect and remove creloaded/cscart backdoor and hacker files

A security expert in creloaded is needed. I need you to find hacker exploit script in my server and all hacker files and backdoors left wwhich he is using to reaccess my server. I need this work to be done with guarantee as it seems like other security experts had some problems rectifying the backdoor even though they did a good job at rectifying some of the backdoors and closing them up. I need a sure guaranteed answer to stop the hacker. After this, i pan to break up the server and go back to regular shared hosting on each sites. There are about 12 sites on the server and i need this work to be accomplished asap. We were able to stop hacker from changing paypal email and extra order info emails but all of a sudden he has been sending customers email from my server requesting information so i need a guaranteed fix to issue. It is obvious he has left several files, exploits and backdoors on the site. I can use paypal or escrow.