How about the Central Hotel in Glasgow?

Tripadvisor via Footstompin

The floor being closed due to a gruesome suicide was well known at the time, but I don't know anybody who stayed there.

The worst I've experienced was in Ordu on the Black Sea coast of Turkey, where I got dropped off at 4am in 1981 because the bus company had told me the wrong journey time. It was pouring with rain and there was only one option. The roof leaked and a streamlet ran across the floor under the bed and out the door into the hallway. The mattress seemed comfortable enough at first, but it was actually a stack of very thin mats, forming a gigantic flea sandwich. I spent another night there (after getting a large can of insecticide from the local pharmacy and blasting every layer of the bedding with enough chemicals to stop a locust plague) but spent much of the intervening day dodging police informers.

This is my Tripadvisor review of the Hotel Avion, Brno.