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Hi Mongos, Smudge, Goofy. Smudge - there seems to be several types of smells - one caused by the fact they keep blocking the drains, by putting animal fat from cooking down it. The man from a drain clearing company has explained to them that that's what the problem is, but they won't listen. Another smell comes from strange things they cook - dried fish (yum!) and god knows what else, but somehow the smell seeps through into our house. And the third problem is that, although the floorboards are plain, waxed (originally) they clean them twice a day by chucking a bucket of water over, and sloshing it about. So the floorboards are rotting and it is all damp underneath. This is partly why the landlord is trying to get them out, as they are wrecking the floor. The landlord also what to get their home back, to move back in.
The tricky thing is - how do you measure a smell? It comes and goes, usually worst about 4.30 when they start cooking, and running water.