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I’m afraid the situation here is not particularly favourable because although you can apply to the Rent Tribunal to have a fair rent set at the market rate, the reality is that if you get a rent set by the Tribunal which is lower than the landlord wants, all the landlord will do is give you a section 21 notice to quit at the end of the term or if the tenancy has become periodic, to quit in two months time. So you can win the battle but actually lose the war. I’m sorry, I know it’s not the answer you wanted.
.Can I clarify anything else for you? I’m happy to answer any specific points arising from this.