Nonsense people: only wanting to find out problems and pay cheap, damaging hosts' reputation. Example: there obviously is hot water, but they did not understand that it must be turned on neither they told me. They preferred to stay one week with cold water and leave a negative feedback. Contrarily to what they said, they did not look for help, they preferred to express personal judgements and to keep looking for problems (at the end of their trip, they left me a separated bag with any possible dirt that they were able to collect into the apartment, so psyco). However, when I refunded them some money (because they did not ask for any other help) they did not say anything more.
They did the same with everything, even if the final price for them was less than $300 for one week in Copacabana.
It is regrettable and sad what such people do, but in the next reservation I will start to filter those type of people.