My boss was on his way out to a convention in Las Vegs (can you feel the jealousy in m post?) and asked me to look at and update our current mail box agreement while he is gone. I work for a place like Mail Boxes, Etc. but we are not a franchise. For some reason, it just doesn't seem to work. I have tried switching out the last "which" for a "that" and it still seems awkward. What do you think?

"A notice will be placed in customer’s mailbox for all certified, registered, insured or COD items, as well as parcels received through any carrier in which an attendant was required to sign, which in turn must be signed by mailbox holder or their designee at the service counter."

How about:

"A notice will be placed in customer’s mailbox for all certified, registered, insured or COD items. In addition, any parcels parcels received through any carrier, where an attendant was required to sign, must in turn be signed by the mailbox holder or their designee at the service counter."

Thanks... except for the typo with the second "parcel" Ha ha