The splattered mess on the back wall of the shower-stall appears a good second before the lady audibly farts, and a very noticeable moment before she even leans forward fully to sneeze (and simultaneously fart).
When Rick is sitting outside the coffee shop talking to Leigh, the same extra walks by at two separate times during their chat. Same entry and exit point on the screen both times. It was a woman in a purple top and blue jeans with a purse.
When Rick goes into the gym to sign-up, the assistant gives him a clipboard for his details, but there is one already there (possibly from a previous take) which he goes to fill in instead. In the next scene, there is only one clipboard.
After golfing when driving on the road in the golf cart they stop at an intersection and wait for a green light. When they start to drive you can see the crossing indicator behind them turn to walk indicating they start to drive when the light just turned red instead of green.