The Barn at Daubeneys is in Colerne. It's a single-storey barn, so it's all on the ground floor. That's handy if stairs aren't for you.
It sleeps four. Two bedrooms, one bathroom. It's got a 4 Star rating. It's a proper conversion, so it's modern inside but you can still tell it's old. The ceilings are high and it's light. You get your own enclosed garden and patio area with a barbecue.
There's a pub and restaurant literally ten yards from the gate. A shop about 200 yards away. The place is very old, part of the oldest house in the village, but it's been done up with a proper kitchen, wifi, a washing machine and a dishwasher.
You're about seven miles from Bath. It's an easy drive or there's a bus. Chippenham's the same sort of distance. Castle Combe, the one you see on TV, is about a 20 minute drive. Lacock is maybe 25 minutes, same for Bradford-on-Avon. The countryside around here is good for walking straight from the door.
I take up to two well-behaved dogs. Bedding and towels are included. There's a cot and a highchair if you need them. Parking is right there.
Useful links: National Trust Bath, Visit Bath, and Cotswolds.com for the area around Castle Combe.