The rentals agency says our chinese landlord doesn't want them to send anyone to look at the alarm system. Reportedly he said we can easily solve the problem by switching off the alarm at night ! What nerve !!! If he's thinking that he has nothing to lose by not fullfilling his obligations as landlord just because we are finalizing the legal formalities for buying the house he's very wrong as we're still paying exactly the same rent. Still, it's yet another battle and yet another headache.
PS - Our very nice and helpful next-door neighbour (I'm shattered that they're moving out before Summer, but that's another story) doesn't think that there's anything moving in the kitchen: his dog sleeps in the kitchen and that doesn't trigger their alarm. He thinks it's just the sensor that needs some maintenance.