(A word of advice: if you want to keep a surreptitious cat in a flat, make sure it's not a Burmese kitten; they're a rather boisterous breed, and don't like being left alone all day.)
Anyway, it looks like I'll have to stash him at someone else's place, at least for the time being.
Or...
I could keep him for a while.
I've always wanted a burmese, and I'm looking for new ways to piss off my Father.
There's always that Dim Sim plant down in Richmond.
Stash the cat somewhere else, then spend a month playing Pungent Stench, BoltThrower etc, at top volume (promptly turning it down whenever the cops arrive, of course). Then negotiate with your neighbours.
Why not hide the little devil and claim that your computer has a cat program which makes noises at random intervals?