You must present to the wrecker operator proof of being a lien holder [42 O.S. § 91A]. Proof would be a printout from a tag agent showing you as the lien holder as listed on the title, or a title showing you as the registered lien holder. You would also need a Hold Harmless Affidavit filled out authorizing whoever you choose to pick up or tow the vehicle. You will have to show proof of insurance or provide an affidavit of nonuse signed by you. When a nonuse affidavit is provided, if the vehicle is driven from the storage, the driver may be subject to a violation of law due to the affidavit specifies nonuse. Towing or hauling may be the best resource.