Safes are your main source for getting capos. There are currently 7 types of safes in the game with varying capo drop rates.

Free Safe
Drop rate: adjustable with rank (the higher your rank, the higher the chances to get Epic and Legendary Capos)
Free Safes can be opened once every 3 hours for free.

Golden Safe
Drop rate: Rare: 88%, Epic 11%, Legendary 1%
Golden Safes can be opened by using Golden Keys or Diamonds.
Every 10th draw gives a guaranteed Epic Capo.

Mystery Safe
Drop rate: Epic 89%, Legendary 11%
Mystery Safes can be opened by using Mystery Keys, Diamonds or Cigars. The Cigar price starts from 2M and gets higher as more safes are opened.
Every 10th draw gives a guaranteed Legendary Capo.

Nations Safe
Drop rate: Epic 84%, Legendary 16%
Nations Safes can be opened by using Selection Keys or Diamonds. With the Nations Safe you can choose the nation of the capo(s) you'll receive. You won't get any capo of another nation.
Every 10th draw gives a guaranteed Legendary Capo.

Traits Safe
Drop rate: Epic 84%, Legendary 16%
Traits Safes can be opened by using Selection Keys or Diamonds. With the Traits Safe you can choose the Trait (STR, BIZ or TECH) of the capo(s) you'll receive. You won't get any capo of another trait.
Every 10th draw gives a guaranteed Legendary Capo.

Mythical Safe
Drop rate: Mythical Capo shards 99.5%, Mythical Capo 0.5%
Mythical Safes can be opened by using Diamonds.

Precision Safe
Drop rate: Epic 84%, Legendary 16%
Precision Safes can be opened by using Precision Keys or Diamonds. With the Precision Safe you can receive a random Epic capo or one of the specific Legendary capos shown in the picture in the Precision Safe panel.
Every 10th draw gives a guaranteed Legendary Capo.
Precision Safes can be available temporarily. Please keep an eye on the timer in the Safe panel.