It's possible that there were unexplained noises or events during the cleaning. The cleaners might have been using strange cleaning products that had a really strong and noxious smell that made people feel ill at ease. And then there could have been things disappearing from the house while they were cleaning, but it was hard to prove they were responsible.
In this scenario, it's summer and a person hires a cleaning service from Craigslist. The cleaners arrive and seem normal at first. However, as they clean, they start making really disturbing noises in the attic. When the homeowner asks what's going on, they say it's just the old pipes or something. But later, the homeowner goes up to the attic and finds some strange symbols drawn on the walls. The cleaners are never seen again, leaving the homeowner with a sense of dread and mystery about what really happened during their 'cleaning'.
Well, there was a time when a cleaning service was hired for an office. They unplugged all the computers to clean around them but then forgot to plug them back in properly. When the employees came in the next day, a lot of important data was lost because some of the hard drives got corrupted. Also, some cleaning services have been known to bring in their own unruly children while working, and those kids made a mess of the client's personal belongings. Another horror story is that a cleaning crew once used a dirty mop on a white carpet, leaving it stained beyond repair.
In another story, a girl answered an ad for a babysitting job on Craigslist. When she got to the house, the parents seemed really off. They left in a hurry and the house was filled with old, creepy dolls. During the night, she heard strange noises coming from the attic. She was so scared that she called a friend to come pick her up right away.
The unexpected and strange locations in some of the stories are quite scary. Like the abandoned - looking places where meetings were set up.
The most common one is probably poor quality of cleaning. For example, they might just wipe the surfaces quickly without really getting rid of the dirt. Another is when cleaners are not trustworthy and steal things. It's also common to hear about cleaners being late or not showing up at all for the scheduled cleaning.
One scary story is about people responding to a rental ad and finding out it was a front for something illegal. When they showed up to view the place, there were strange people lurking around and they got a really bad vibe. They quickly left and later found out that the police had been investigating the property for illegal activities.
There was a story where a person was looking for a used car on Craigslist. They found a great deal on a car that looked perfect in the pictures. When they went to meet the seller, the location was an old, abandoned garage on the outskirts of town. The seller was acting really strange, mumbling to himself and constantly looking around nervously. As the buyer got closer to the car, they noticed strange scratches on the inside of the windows, as if someone had been trying to get out. The buyer got so scared that they just ran away without looking back.
Sure. There was a case where a girl was looking for a roommate on Craigslist. She found someone who seemed nice at first. But after a few days of living together, the roommate started acting really weird. She would stay up all night talking to herself and would often lock herself in her room for hours. One day, the girl came home and found the roommate had cut up all of her clothes and was sitting in the middle of the mess, smiling. The girl was so scared that she immediately called the police and moved out that same day.
I once read a story from it where a person went to buy a used item. When they got to the address, it was a really creepy, dilapidated house. The seller had a strange look in his eyes and the whole place smelled bad. It was a really unnerving experience.
The unknown makes a summer camp story scary. For example, strange noises in the woods at night. You don't know what's making those noises, could be an animal or something more sinister.