Regarding LV, this crime scene stinks. A bad guy, set on doing great harm, and having this many weapons, would have had them lined up in some type of order, ready to use. They would be more meticulous.
If this was truly a one person event, they would have had plans. This looks like a haphazard crime scene that someone(s) threw rifles, ammo, and spent casing around the room. In other words, this crime scene is staged and utter bullshit. JMHO.