This is a difficult question. Some defects are in any case for the tenant to replace, such as minor maintenance. In case of major maintenance, the landlord is responsible for this. If he doesn't, you can put him in default and fix it yourself. You can think of deducting the costs from the basic rent. However, this entails many risks. What if something goes wrong? What if you don't repair it properly or have it repaired? Who is responsible then?
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