Bluebell Barn is out in Meldon, just outside Okehampton. It's a converted granite barn. It's detached, so no neighbours attached. It sleeps two, one bedroom with an en-suite shower room. It's got a 5 Star rating, which is basically for the modern finish and the underfloor heating. It's warm.
The layout is open plan. There's a kitchen area, a living space, and doors out to a big private patio. The garden is enclosed. There's a hot tub on the patio. You can see fields and Dartmoor in the distance.
Facilities are all there: washing machine, dishwasher, WiFi, TV. Bedding and towels are included. There's parking right outside. The entrance is wheelchair accessible, but inside it's all on one level with a walk-in shower, so that should work for most.
There's a pub about a mile away. The nearest shop and a restaurant are in Okehampton, about three miles. Okehampton is the main town here, it's got what you need and it's the gateway to Dartmoor.
You're right on the edge of Dartmoor National Park. Good walking straight from the door, or a short drive to places like Lydford Gorge. The Granite Way cycle trail is nearby. The north Devon and Cornwall coasts are about a 30-40 minute drive. Beaches like Westward Ho! or Widemouth Bay. You can get to places like Castle Drogo or the RHS Garden Rosemoor within half an hour.
Useful links for planning: Dartmoor National Park Authority and National Trust Dartmoor.