Audit | Management homework help

I am working on an internal control project for my auditing class, and need some assistance on how to create a new system to handle in-store customer returns. Attached you will find the project requirements, along with the case. I think I’ve answered the 1st and 2nd parts of the project correctly, but would like help on the 3rd part.

2 pages  The third part asks me to write a memo to AAGM’s audit committee chair with a proposal on the type of internal control policies/procedures that should be put in place. I’m a little stuck on what kind of controls should be used and strengthened