Dirty smelly sheets in master bedroom. kitchen sink smells like someone regurgitated in it.
Itchy furniture if you're allergic to dust mites.
I took a picture of the filter that look like it hasn't been changed in 20 years. Your rental car will get scratched due to the extremely barrow driveway.
Noisy neighbors partying & walking the neighborhood all night.
You better bring your own tissue & paper towels because you will have to inform the host. This should already be done prior to customer entrance.