As a general notion, the last 3 Collectibles of each Collection - in the case of North America, these are the 'Empire State Building', 'Viva Las Vegas', and 'Man On The Moon' Collectibles - can only be obtained by either:
- Waiting for them to be awarded to you at the street (after daubing on a house), during the Game Summary
- Trading earlier Collectibles for them, in the "Trade-up" window
- Receiving it as a gift from friends
Please note that a Trade-up of one Collectible for another costs 3 of the former and requires that you hold at least 1 of it, after the trade, So, in practice, you are required to have at least 4 of a Collectible in order to trade it for the next