dirtiest home you've been to

I cleaned my dad's apartment today (he's in china rn) and my god, what filth is this man living in.

The countertops are filled with that... oil that has been left out for too long and so it's crusted and hard on it.

The glass thing on top of the stove is like that too.

His microwave oven was a dark brown. When I finished cleaning it... it was clear... clear... CLEAR

but yknow, only the places he uses are dirty, so there are a lot of these 'spots' where there's only this layer of dust... because he never uses it.

I-

SO anyway, dirtiest place you've been to?