Free advice from the Berlin Tenants' Association or other tenants' associations.
What the Berlin tenants' associations offer in terms of advice and legal protection.

There are many tenant organizations in Berlin. The three largest are the Berlin Tenants' Association, the Berlin Tenants' Community, and the Berlin Tenants' Protection Association. They offer weekly legal advice on tenancy law in all Berlin districts. The consultations are free for members. Appointments usually need to be made by phone.
During the consultation, lawyers from the tenant organizations can help you. They will review your case, answer your questions, and advise you on the next steps.
If you have legal expenses insurance before you signed your lease, the insurance will cover the costs if your case goes to court. If you become a member now, you can receive free consultations. However, if your case goes to court, you will not have insurance coverage.
Why tenant organizations are generally important:
Tenants' organizations are there for us tenants. Tenants from all over the city meet here to fight against high rents.
We have been working with the Berlin Tenants' Association for years. It's worthwhile becoming a member of the BMV and organizing in the district groups to fight against the rental crisis. We need strong advocacy groups so we can stand up to the large housing corporations.