When the flat upstairs has leaked into your property repeatedly and communication has broken down with the owner who refuses to accept responsibility (and pay for the damage and insurance excess) what is the next step?
I think you will need to take the neighbor to small-claims court. A friend of mine was the upstairs neighbor in a situation like this, and neither party really was in the right in her case about what was wrong and who owed what. In your case, professional mediation (yellow pages) might even work. However, don't delay just because this is a nasty situation: procrastinate and you will lose out.
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