Rented a managed flat from spark and sons. We had a broken toilet for two weeks. When we called to remind them of the problem, they did all they could to get you off the phone. They clearly didn't write any notes or do anything about it until we actually visited them in person. The exact same thing happened when the fridge broke (it was furnished flat). It was a battle to recover the deposit. Visited them in person, made a fuss and got the deposit back.
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