When Renko shoots Iamskoy and the public baths, Iamskoy falls backward over the railing. He starts to fall straight down, which would be logical. But the aerial shot shows him landing out in the pool, in the water, several feet from the edge of the pool. He should have landed on the pool deck, not in the water.
When Arkady's car stalls on the bridge on the way back to Moscow, the wipers are still running. As Arkady repeatedly tries to re-start the car, we see the wipers still running at full speed. In real life, each time he tried to restart the car, the wipers would slow from the drain of battery power away from the wipers to the starter motor.