Ok boys. Here's how easy this is.
All AR type rifles break down into two parts: an upper and a lower. There's further disassembly that can take place like removing the barrel and quad rail around the barrel. Once this is done, the components would fit nicely in a big ol' hard cover golf bag.... or two.
So, you pull your suv into the parking lot, your guns are disassembled in the back of it. You've already got two golf backs filled with guns and a rolling bag with mags and ammo.
You check in with golf bags and rolling bag and head up to the room. You're here to play golf.....it appears to everyone at the front desk.
So after you get settled in, you empty your bags and a little later, you head back downstairs with your golf bag. Head over to your car and fill your empty bag up with more guns. With all the comings and goings you decide to take a different elevator set back up to your floor to avoid people at the front desk going "didn't he just leave? And he's already back?".
You head back upstairs, empty your bag and relax for a while. A couple hours later, you go back down the new elevators, walk to your truck fill the bag again and this time go back by the front desk as if you're returning from your three hour golf outing.
This is "trade craft" and it's simple.