Continuity
When Sam is rummaging in the medicine cabinet sometimes his second set of glasses is on the top of his head at other times they disappear.
In the rental car the position of the driver's door lock changes out of sync with the movements by Sam.
At the pool Billy's Aria swizzle stick appears and disappears between shots.
When Ezra gives Archie his pill box, the colour of the compartments changes from blue to red and back to blue.
When Paddy hits a guy at the nightclub, his right fist is bleeding. Few moments later at the hotel room it's the left fist.
Errors in geography
After discovering that Binion's had no rooms, they headed to Aria. in the next scene, they are walking with their luggage on the strip heading north up the strip away from Caesars palace. Aria is in the other direction, south of Caesars Palace.
Factual errors
When Archie buys in at the blackjack table for $15,000, the pit boss would have stopped the transaction and asked him for ID and his social security number. Any cash transaction of over $10,000 requires this.