FD, you’re circumstances are remarkably similar to mine. My Mum has been looking into options for some time and after taking advice she’s concluded that putting the house into a trust, with me/my sister as the trustees is the best option.
Afraid I don’t know the finer details of all options she considered but the down side of this one is there’s a cost to set it up (around £1k I think), but it’s peanuts compared to what you might save in the long run.
As for comments above criticising you for looking into this – it’s simply naive not to plan for something that’s inevitable, albeit unpleasant to face, and just hope it all works out for the best. It won’t and you’ll finish up paying far more than you need to in tax & health care fees.