Despite friendly, helpful owners, fundamental problems with flat (did they hired wrong contractors?). Should not be rented.
Most important issue: extreme HUMIDITY. -1 level. No air circulation (+ leakage?). Water damage. Smell. Industrial dehumidifier (which was present😕) detracted 4L per day. Unhealthy environment. STRUCTURAL problem. Feel bad for nice owners.
Other issues:
-No light outside, very dark staircase, danger
-1 window can't open/close
-Kitchen cabinets & wardrobe poor quality/installation: hard to close
-Dishwasher installation incorrect: tips over!
-Dishwasher broken inside. Elements don't fit. Almost unusable.
-Poor-quality devices, eg microwave impossible without manual
-Oven unusable: button broken off (poor quality)
-Coffeemaker & shower chalked, broken
-Sofaset broken
-Very little sunlight
-Washing machine always occupied
-Dirty, too long curtains
-No privacy
-Day & night (!) construction workers in neighbouring flat of same owners
-Key not where communicated
...