The money that Keith Tobin puts in the box is clearly fake, looking nothing like US currency.
Officer Dennis says Merchant was shot at close range by a small caliber revolver, and that the ambulance and medical examiner were on the way. Since no ballistic analysis had taken place and all Dennis would have seen was a bullet wound, he would be unable to determine the caliber nor the type of gun used.
When Ed pulls up in front of Keith's house he pulls a piece of paper with an address on it out of the glove box to look at it. He holds the paper so the camera can see it rather than angle it toward himself.
When Dan Mathews knocks on Ed Tobin's door he walks in before Ed Tobin invites him in.