You are very welcome to stay with us ( three two-legged and three four- legged ) in a single room. Our house is near to Altstadtbahnhof and about 10 minutes to the city. It is easy to walk there or catch a bus nearby.
I also rent out another room in our house. Perhaps you could have a look at those offers: one is " spacious room in big garden" and the other one "Türmchen" but that is only available in summer :)