The two suitcases Walker removes from the motel room are obviously empty. The weight of 36 rifles and hand guns is so substantial that the cases could not be one-handed into the trunk of a car so easily.
Fully automatic assault rifles cannot be purchased "over the counter" anywhere in the US. They require a special license from the BATFE which takes about a year to run the background check on, and a special tax stamp for each rifle. Very few gun stores even carry assault rifles that are legal for civilians to own, and they start at about $20,000. If they sell them, they would usually only have one or two for sale at any time, not in the quantities shown on this episode.
When Hawley forces his way into the Camerons' motel room, a car parked outside bears the New York license plate F3L 60E4. In season 2, this plate was on one of the FBI SUVs.
When the team is about to surround the bad guys, Remy says "Calvary's coming." He should have said 'cavalry'.