Sorry for the delay guys, I nodded off. I'm off to bed for the night in a min, but wanted to address the question above. We didn't move out until now because, literally, in the last six weeks or whatever it's been we went from seeing 'a' mouse and setting traps appropriately, to becoming literally over-run.
You don't leave home because of a single mouse (most wouldn't anyway), but once it's clear you suddenly have dozens, you do.

Rentokill said it's likely a combination of one or two mice quietly moving into the cavities somewhere and giving birth, and the babies then 'spilling out' into the house, and the cold weather meaning several mice have sought refuge here due to the ease of access.
Therefore, we went from 0-eleventy million in a week flat, or so it seemed. If that seems implausible please remember we're talking about a large detached house literally joined on to a large farmer's field. One moment we had a mouse in the house, the next they were waking us up in the night chewing the bed base and running all over the place. :\
It's not as logistically simple as some are making out, nor do we have the cash to 'just' store possessions somewhere else or walk into another property. It's all very well to say if we have children we 'must' have savings, but when you're essentially living hand to mouth on a week-to-week basis it's not so easy. If we had a flat-screen TV to worry about, I'm sure we'd have saved it.
As it is most of the damage has been done via chewing and soiling, and as 99% of our stuff is at 3' or below, they didn't have to too work hard to get at it. The result was rapid carnage. Until you've been cast suddenly into such a situation, I'm not sure it's fair to cast aspersions about how it 'should' have been handled. When you're moderately/severely disabled, struggling with three children and trying to crack on with a degree, your resources are rather stretched and definitely finite.
The report from Rentokill says we did nothing to encourage, and everything to discourage, the infestation, and that it was both rapid and overwhelming. It feels like we went from living happily and comfortably, to being in some kind of bizarre sick movie plot inside a few days, though in reality it's been a bit longer than that.
Immediately as soon as the problem became clear we called out Pest Control, Environmental Health became involved, and we (under their advice as to how bad things actually were) wrote a formal letter to the agency and advised them of our legal position. Once words like 'rent withholding' and 'statutory liability' started being banded about, it's amazing how quickly they decided to call Rentokill and 'get things done'.
As it turns out, it was too little too late. The posts asking about why we didn't get the disrepair sorted sooner are missing the point. Until you actually have cause for alarm (i.e. mice), are you
really going to be going mental about getting bristle brushes installed under the door you never use at the other side of the property, or the fact that the pipes enter the house through holes slightly bigger than them? Little things which were previously rather insignificant on their own suddenly take on a large role in exacerbating the problem.
Now that the house
is infested, it's been deemed that there is a hell of a lot that needs doing to the house before the mice can be tackled. There's literally not much else we could have done, nor any sooner, short of being prophetic and insisting they fixed it before it happened.