Large double room in Llandovery

I am a retired teacher living in a three bedroomed house with a young cocker spaniel and a cat. I am wishing to let out one of the double rooms fully furnished. I am open to letting the room to a couple on a short term basis, although this would mean an adjustment to the rent. I am open to short or longer term lets and I am happy to be flexible.
Llandovery is a lovely, friendly town, with various pubs and places to eat out. The house is in a quiet residential street five minutes from the town centre.
Ideally the room would suit a non smoker, but I have no objection to smoking in the garden.