Apartment was very dusty. Three of the occupants had severe allergies whenever they were in the apartment. Symptoms included runny noses, red/watery eyes, and itchy skin.
The water pressure in the shower was very weak. Some of the girls had to resort to washing their hair under the faucet in the bathtub.
There was not enough hot water for all four occupants of the apartment. Some of them had to take cold showers which in winter is unacceptable.
The door to the bathroom could not be shut and properly locked. This is a security/privacy issue especially since the group of four are of mixed gender.
There were not enough towels upon check in. It was rectified later when additional towels were delivered. This was the only issue that the host addressed.
Towel rails in bathroom were broken which was a potential safety issue when floor is slippery.
Mold on the bathroom mat was a potential health issue.