My worst experience with an apartment.
On my first day, when I came back in the evening after exploring the city, I noticed someone had gone through my bags and an envelop with cash in Chilean pesos (hidden in an inside pocket, not in plain sight) was missing.
This had never happened to me before, not even in hostels...
Minutes later, I was meeting the property manager to pay for the apartment. I explained the problem and asked who had the keys to the apartment. Apparently, only the cleaning staff does, but the apartment hadn't been cleaned anyway. The property manager then explained they didn't change towels or make beds (...so why would cleaning staff come?).
This is the kind of situation were absolutely no solution can be found and I definitely wouldn't blame the cleaning staff (too easy!). The property manager's only offer was to ask the cleaning staff not to come "clean" the next day.
I didn't feel safe and comfortable in this apartment where apparently several people had the keys, so I paid for the two nights and left the next morning. The property manager never apologized, explained or offered help.
When I left, the front desk staff asked me why I wasn't staying for the week as planned. I told them and they didn't seem surprised at all.