Authorized.net Integration and bug fixing

We have a Wordpress site which uses a plugin for ecommerce. We need someone with experience in integrating [login to view URL] Advanced Integration Method (AIM). If you are not familiar with the term or haven't done it before please don't apply. This needs to be done asap. Someone was hired earlier who claims that the integration is already done but we are still facing problems. I need this done urgently so if you are not available to start and finish asap please don't apply. Budget: $30