Here's a spare room I have. This is before I lent it out (free of charge) to a friend and her kids because she was down on her luck.

This is what she did to the room...

And this is what I did to fix it. After nearly a $100 in cleaning supplies including the price of renting a professional carpet cleaner and a lot of scrubbing on my hands and knees... The results...

I'm exhausted. I have blisters between my index fingers and thumbs and carpet burns on my knees from scrubbing and scraping junk off the floor.
I'm very annoyed with her. We got into a disagreement today. She didn't like that I reprimanded her. (she borrowed my car late at night supposedly to go down the street momentarily but instead didn't come back until 9am costing me $50 in Lyft charges and causing me to be late for work) she's claiming she's moving out. I pray she does without causing me any more issues. She told me she packing up and was leaving. Well she left alright... she's been gone all day but she left her mess her dog and... Her kids here with me to tend to...
Ridiculous and irresponsible!