University academic looking for a room Mon-Fri

I am an academic at the university of Lincoln. I'm looking for a double room in a nice flat or house, with quiet, clean friendly housemates. My preference is for a smaller share with no more than 3 housemates - all professionals or postgrads, not students! It needs to be central (walking distance from the train station and university). I will be working in Lincoln during the week but not living there full time, so I won't be around that much. It's likely this will normally be just 2-3 weeknights during term, although my schedule will be flexible and I'll have to spend the occasional weekend. I'm looking to share initially for 6 months while I get to know Lincoln, but may well extend this beyond that.