Theory, mine:
I think Barry used bromide over MDW.
I think it caused irritation. I think it left him smelling like chlorine, something he hadn't anticipated. I think HE smelled like a hot tub and didn't even realize it until his first recorded trash stop. I think bromide might also have stained his skin.
I think he parked along the side of the hotel specifically to avoid hotel cameras. Wanted to bypass the front desk because HE WAS RANK. I think, had another hotel guest unwittingly let him in (assuming Barry was a paid guest), Barry would have showered in the pool shower. How ever many times and towels it tool.
He was forced, however, to pivot. Had to come in through the front door. I'd like to see that footage. I'd like to hear his first conversation at the front desk. Accounting for his stench, if he had to.
I really don't think the hotel was supposed to feature so strongly in his day. He had evidence to discard, he had a job site he wanted to use as an alibi.
I think the hotel became a necessary detour because of, first, the need to shower repeatedly and, two, The Call was delayed.
Otherwise, I think Barry would've spent his time between the wall and trash runs. Busy, busy B. Remove a capstone, dump a bag, remove a capstone, dump a bag.
IMO it's the lather/rinse/repeat in between that messed that up.
Because IMO he planned to show up at the hotel ONCE. To leave tools. Early afternoon. Like 1.
Didn't get a lot of work done because he wasn't there long enough. As if.
Wouldn't need to adjust reservation/check-in. Show up once, having actually come from his work site.
Since IMO he was forced to get to the hotel early (to shower, over and over), he tried to use it to his advantage. Convince the person behind the desk he was working hard, back and firth to his worksite, with workers present.
I don't mean to belabor the point.
I mean to belabor bromide.
JMO