Well it now looks like we'll be moving before the new Muddle makes an appearance! Our landlady kindly gave us the minimum possible notice of a whopping 8% rent increase. She then negotiated slightly lower but we suspect her reasons may have been less than truthful (well, I've not heard from anyone else who's mortgage has gone up due to interest rates recently...) and as we were paying top whack for this place anyway we've decided to look for something more affordable.
On Friday we put in an application on a house very near us, with very similar proportions to the one we're in now, just with a much smaller garden. Hopefully we should hear back in the next couple of days but I'm on total tenterhooks. It would leave us a lot better off financially, while still being a relatively future-proof option for us (that is as long as this landlord doesn't start paying more attention to his bank balance than the actual market values!)