I used the hotel kota 5 mins walk from maliaboro.
Don't let the taxi drivers suggest hotels. They will always take you to the one that gives them a kickback regardless of how much good it is to you.
From the airport. Take a taxi to Maliaboro and take the first right where the circle K shop is. Walk around there and the next street down until you find a place you like the look of. Loads to chose from that are cheap, clean and tidy. Most have English speakers.
From the train station, walk. It talks a few minutes or just turn right out of the station and walk on the left hand side of the road until you see one you like. Plenty there below Rp200,000 and most less than 150,000/night.