I have stayed for almost five months at Mona's place. She is a wonderful host. As a tenant you have access to the lower level (private bedroom and bathroom). Both rooms are nicely decorated and everything is extremely clean. On a more technical note, the wifi connection is reliable as I've never experienced any problems. The atmosphere in the house is generally calm and quiet, which I really enjoyed, especially after a though day at work. However, if I needed help or felt like talking, Mona was always there for me. Her place is located in a safe neighbourhood and everything was more or less in walking distance (the supermarket and the red line are only a few minutes away and MIT is approx. 15 min). The airbnb stay comes with a lease agreement (= house rules), although one could say she is strict about these rules, it clarifies what the tenant can expect during the stay.
In summary, I have definitely enjoyed my stay and if I ever revisit Cambridge again, I would certainly stay at her place again! Therefore, I highly recommend this place to other AirBnB'ers!