I lived in a co-op and we were allowed to paint our rooms provided we used officially approved colors. I had stopped painting my room for the day and cleaned up. I thought I had tamped down the lid sufficiently. I went to bed. The next morning when I bolted up to turn off my alarm, I kicked a can of bright green paint that I had thoughtfully placed in the middle of the room. Thud. Gloop.
Naturally, I wasn't gonna tell anybody as it would be quite expensive to replace the carpet and if I could just clean it up sufficiently that it would fly under the checkout person's radar, I would be home free!
Fortunately the carpet was that industrial blue stuff that hides all sorts of dodgy stains.
Renting a wet vac was right out. "What's that for?" "Uh..." Fortunately, after a couple of days of pouring water on the floor, stomping it with a towel or dark-colored cloth, rinsing it out, partially drying the towels, scraping the floor to see if there was any residual paint, blasting the fan and ironing the floor dry so it wouldn't start rotting (there was already a noticeable mildew smell), I declared the carpet passable and let it be.
After it dried, there was a large faint crunchy stain in the middle of the carpet along with a faint mildewiness that lingered for a while.
I got my deposit back. The new resident never made mention of it. I vowed never to paint again anything that involved a deposit.