To obtain a renewal permit you will need a Permit Application signed and notarized by the original contractor only. If the permit was done by owner then only the owner's notarized signature is required. You will be charged a renewal fee according to the current fee ordinance.
If you cannot find the original contractor and you wish to change the contractor, both the owner and the new contractor must sign and notarize the Permit Application. You will need to indicate that this is a change of contractor for an expired permit in the description of work on the Permit Application. You will be charged for the renewal and change of contractor on the same application according to the current fee ordinance.