What is the best thing I can do to resolve my situation with DUWO housing?

Questioner

I live in a building of student housing corporation DUWO. We have been struggling with hot water problems as a whole building for almost 2 years and they seem to be worse in the winter periods (worse = more often no hot water). DUWO keeps promising that a solution will be found, but after 2 years there has still been no progress. In addition, we had 8 power outages in September and October, where they only wanted to start research after the 8th time and the research can only be carried out during the next power outage because they have now installed measuring equipment (fortunately, it has not happened a 9th time yet). This causes problems with no wifi and now that we are all students, wifi is important for online lectures In the meantime, we have to continue paying the rent and we do not receive any compensation for, for example, power outages, because we purchase electricity collectively (which is included in the rent) and therefore receive a discount every month. But that doesn't mean that these problems don't bother us. I wonder what I can do best because I don't want to wait for DUWO to come up with a solution. Is it useful to set up a lawyer here?

Lawyer

If there are defects in the rented property (including communal areas and the functioning of installations), the tenant can suspend part of the rent as a stick behind the door. I advise announcing this in a letter in which the defects are again mentioned and various dates and examples. Give x time to solve these problems after which follow-up steps can be taken.