I fell behind on my car payments, so the bank repossessed the car. As the repo man was hooking up my car to a tow truck, I tried to get my things out of the car, including an expensive sound system and my iPhone. However, the repo agent refused to let me get my property unless I paid him $20 as a “convenience fee.” Is that legal?
Probably not. While you might be liable for fees related to the repossession and auction of the car, the “convenience fee” is not one of them.
You are legally entitled to your personal property. The car loan lender must return that property to you because it doesn't have a legal interest in it. (The lender only has an interest in the car, which served as collateral as payment for the car loan.) This obligation extends to the repo agent and anyone else that the bank has hired to repossess and store the car. The repo agent should have let you retrieve your personal property before towing the car.
The only exception to this rule is if the property was attached in some way to the car. You mentioned wanting to get back your sound system. If the system was installed in the car so that you'd need tools to remove it, then you probably would not have been able to take it back, anyway. That's because the sound system became a fixture to the car, and fixtures become part of the car that the bank can legally take and sell.
If you have not done so, you should call the creditor right away and make arrangements to get your property back. If it refuses, or if the property was lost or damaged during or after the repossession, then you may have a claim against the creditor for damages. You may also use that as a defense if the creditor later sues you for a deficiency judgment after the car repo.
To learn more about your rights, see Can I Get My Personal Property After Repo?