When we take the Security Deposit on your credit card, your bank holds back that amount from your credit limit for 7 days.  We do not actually touch it or have anything to do with releasing it, as it is all automatic.
If the bank does not hear from us about any charges, then they take care of releasing the money back to you on their own. If you return damaged items or you lose something, then your card will be charged the amount that Jack of all Spades deems fair, and the bank will release the remainder back to you.