First what is the difference between a refund and a reimbursement?
A refund is when a member has a credit balance on their account due to overpayment or reversal of charges. This will show directly on their account.
If they are receiving invoices in the future, you can leave the credit on the account to be applied to future charges. If they are not getting anymore invoices in the future, or they have requested the credit balance be refunded, you can process this via payables.
You would add the member as a payee and create a bill for them for the amount of the credit balance. You would then need to add an invoice to their member account to zero out the credit balance.
A reimbursement is when a member has paid for something on behalf of the chapter, supplies for an event, a bill etc. that they are now getting that payment returned back to them.
For this, you will follow the same procedure as a refund - add the member as a payee and create a bill for them for the amount of the reimbursement. Unlike the refund though, you will not need to invoice the member's account, as no credit balance will exist to zero out.
* Security Deposits, for reporting purposes, should be handled as reimbursements.