Print out the letter to 10 copies, envelope them. Go to apartment in the address. Because the apartment is locked, so wait for hours, maybe days at the front entrance until someone open the door. The residents tend to leave more on afternoon and evening and on weekends. Ask them to get inside to deliver the matter-of-life-and-death important mails for one of their "linked friends". Deliver mails to 10 specific doors directly to the receivers. Apologize getting inside the building without their permission (They are the building managers). Tell them the mails are urgent business. Get proofs of deliveries to each door. Send me proofs of deliveries.