Experienced hoteliers John and Lee Cox have bought the Lansdowne hotel in Brecon, off an asking price of £375,000.
The Grade II-listed Georgian guest house, which has nine rooms, is set to reopen in March this year with the new name of Ty Helyg Guest House.
The deal was brokered by property agent Colliers International.
Lee Cox said: "My husband John and I moved back to Wales 10 years ago and have big plans for the business.
"It's in a great position near the centre of town but it does need a bit of a lift. We will be drawing on our time in the London hospitality sector to give the hotel a slightly more contemporary feel, with Georgian overtones, and aim to offer a four-star guest house for tourists and business visitors."
Peter Brunt, a hotels director with Colliers International, said: "Brecon is a great spot for a good B&B as it offers a handy base to explore the thriving market town as well as the fabulous surrounding countryside.
"There is a good mix of rooms as well as particularly attractive living accommodation for the owners."