When Craig comes to Day-Day's job to give him the tax notice, watch as Day-Day opens the envelope. The address starts with "7700". Now fast forward to the scene where Day-Day, Craig and Roach come back to Day-Day's house and they pull up into the driveway. This scene shows all the addresses on the mailboxes for the whole court. The "purple" mailbox which is Day-Day's house starts with the numbers "276". Definitely a Slip up!