At the end of the film, when Jacob/Money receives the letter from his son, it's addressed to 'CA Rehabilitation Center' in Norco, California. Indeed, there is a California Rehabilitation Center in Norco; however, it's mainly a rehabilitation center for non-violent, low-level drug addicts--definitely NOT a facility where a hardened, gang-connected, violent criminal would ever be housed.
Before his capture towards the end, Money internally conceals a capsule containing a razor. Given that following his arrest he would still have had to go through a trial and processing, it's hard to believe that he could have successfully concealed this for the weeks or months this would have taken.
After Money kills Shotgun, as he's cleaning up, Shotgun's phone goes off. Money takes it and reads the text, types something into the phone, then attempts to place the phone back in Shotgun's dead hand, but can't quite slide it in. Shotgun's hand suddenly opens, his fingers stretching out, to grip the phone. Excellent dexterity for a dead guy.
During the fight between Money and The Beast there is a shot of The Beast with his right hand held on the ground by Money, on the next shot the hand is on Money's throat and he forces it to the ground.