The Mill House is right on the main square in Talgarth. It's a detached cottage from the 1830s. It used to be part of the mill, and the dining space was the local butcher's shop. You're in the middle of town, so you can walk to the shops and pubs.
It sleeps five. Three bedrooms, one bathroom. It's got a 4 Star rating. The entrance is wheelchair accessible. There's a walk-in shower over the bath.
You've got a dishwasher and a washing machine. Bedding and towels are included. The wifi usually works.
For walking, you can go straight out from the front door. For a bigger walk, Pen y Fan is about a 20 minute drive. Brecon is nine miles away. Hay-on-Wye is eight miles, that's the one with all the bookshops. Cardiff and Swansea are both about an hour if you want a city day.
Useful links: Bannau Brycheiniog National Park and Talgarth Mill just down the road.