Each Co-op mission offers experience points, coins, and a prize that can be placed on your farm.
The number of XP, coins and the specific prize are dependent on which co-op job is completed, as well as the amount of time taken. The Gold medal level receives more XP and coins, as well as a special prize. The Bronze medal level receives less XP and coins.
All members of the Co-op get the same reward even if they do not contribute, and regardless of the number of members. A maximum of 10 neighbors may become members of any Co-op and a member must wait for the Co-op to be completed, or quit the Co-op, before that person can start or join another.