Mr. Earl Brooks (Kevin Costner) uses a stainless Walther PPK/S fitted with a sound suppressor as his weapon of choice to murder his victims. He "bags" the gun by taking a large freezer bag and zip-tying it to his wrist, preventing the ejecting shells from being left at the scene. It clearly shows his level of profession because leaving a gun zip-tied to your arm leaves one arm useless and makes it almost impossible to reload, so he must obviously know exactly what he is going to do, or else he would be a rather reckless killer.
Mr. Smith (Dane Cook) uses a CZ 75BD pistol to threaten and attempt to kill Mr. Brooks. Brooks contemplates letting Smith kill him, relieving him of his sickness, so he puts two CZ 75BDs in the scenario. He leaves one in Smith's apartment, the firing pin bent to prevent it from striking the primer, rendering it useless. The second is a working, loaded one kept in a shoulder holster on Brooks' person. Brooks decides he wants to live to watch over his family, including his pregnant daughter, and leaves Smith with the useless CZ.
