Come round my house, count the cracks and tell me you still want to buy a house with subsidence!
When we moved in, it was visible in x2 places: where an extension joins the lounge. The owners were aware.
In the space of 7 months there isn't a room at the front of the house that doesn't have very visible cracks in every room, both inside and out, above and below windows, across ceilings, along skirting boards in some places. The patio terrace at the back has heaved to an alarming degree, the steps have cracked (and are pulling away from the house AND sinking), and even the asphalt out the front of the house has a gigantic, seam like crack in it. The terrace patio at the back is pulling away from the extension, there's a 1 inch gap.
Seven months. It's genuinely shocking.
Now, when we moved, we could only find ONE insurer who was prepared to quote us for contents insurance. We thought it was because we're on a river (around 7 metres away and 4 metres above it), but have since learned that all the houses are subsiding. So, it's more likely to do with nearby subsidence claims than their risk adverseness towards a river that has never flooded.
Added to that, the cracking and popping noises the house only seems to make in the middle of the night really get my back up - they're always at 3-5am and wake us up.
We paid more than seven times I have ever paid for our contents insurance: £330. That's not even to insure the house.
So, I'd have little faith in just being told to monitor it. Certainly, I'd need to know the cause and I'd be talking to all the neighbours about the history of said house and their own houses.
(we are renting, I'd never buy this house, not even at half its market value)