Hmm...
"What's that randomly placed panel that's partly obscured by your bed headboard ?!?"
Ah, the utility of interior design (decorating) versus the utility of, um... utility!
I remember seeing old houses from the 1920s-30s that had access panels everywhere one was possible (interior access only, no panels through the wall of the house from outside
).
The house I built I put a tub and shower access panel in an adjoining room.
In this house I had to cut and put one in due to a leak. A stub wall in a bathroom, tub and shower one side, the access panel side is into a toilet area. Tempered 1/4" hardboard makes for a thin panel, surface-mounts over the access cutout with a few SS pan head screws. Primed and painted the panel first, including all edges, and well-dried before installation.
Had to do another one down inside a closet/cabinet in a different bathroom, through the stub wall on one side to the plumbing end of another tub so termite guy could get at the little munchers.
Eventually, when I do a big bath renovation, I will have to put an access panel behind a shower stall. That one goes into a closet with a big custom-built built-in storage in it. Won't be fun to do that, but probably a nit in the whole project effort by comparison.
Once I took down a big bathroom wall mirror over a dual vanity in someone else's house to get to a PVC vent stack for dual sinks. Cut in there and put a cleanout and snaked and flushed a blockage that was between floors and horizontally about 20' away. Luckily the mirror wasn't glued to the wall, just clips. I cut the drywall centered on two studs, and then slipped in two pieces of 1x4 for drywall attachment with screws for top and bottom of new drywall piece. Then the mirror went back up. The blame goes to the plumber who did DWV when it was built. He used a simple 4-way cross to collect the two in-wall pipes from each sink into the down-sewer pipe and the up-vent pipe. Disconnect either trap from wall, and try to snake, the snake just went across the cross to the other sink! DUH! Un-snakeable as built!