Rewards you earn in the game can be found and collected in the Gift Center. You can find your Gift Center in the lower right of the main lobby. You will be able to check your Income, Gifts, and Invites for the game.
Your Income shows rewards you have earned like MONOPOLY Bucks or Coins! Your Gifts show gifts from your friends and residents in the city. Your Invites are opportunities to invite your friends to play with you!