Remote P/T Billing/Invoicing using AutoTask, Quickbooks for IT company

Looking for a part-time person who can work remotely and help an IT company do it's monthly billing & invoicing work using AutoTask and Quickbooks. Past experience in these applications preferred but not mandatory. The person needs to be very detail oriented, good in written/verbal communication, accurate and dependable/diligent. Approximate hours/month: 50-70 although it can vary.