Jeffrey,
There are some organizations out there that could assist you in automating this process; however, it may be easier for you to develop an internal process to handle your students. The decision to keep internal or outsource handling of credit balances really reflects on the needs of your students. Overall, it seems that you have aprocess to evaluate your system efficiencies and that is a great process to have in place.
Sincerely,
Chyrl Ayers