u/bitb0y

We are moving into a new apartment soon, and while the rest of the apartment is great in every way, the bathroom has this. The people (younger, 20s) who currently live there said they've tried to clean it without luck, and that the management company has successfully cleaned it but that it returned a bit later. Are there any extreme products I can use on this to mitigate the issue? Thanks all.

(Ps sorry for the crappy photo, it's a still from a video I took of the apartment)