Overall very comfortable room in a safe and quiet neighborhood! We were able to leisurely use only public transportation during our stay. (15 min walk to the T, 5-8 min walk to bus stop).
I put 5-stars for everything except accuracy and value: for accuracy, I noticed the workspace was more of a side-table with a sofa chair. So, if you're looking for a place to write documents or work on your laptop, this setup probably isn't the most comfortable for you. The A/C is also controlled by the host since the entire house has an HVAC system (although she is very responsive and accommodating, and included an extra powerful fan for flexibility).
As for value, I'm unsure what Boston's AirBnb policies are, but the price of this space is about the same as a similar hotel room closer to central downtown. Since this room is attached to the host's house, you won't get a lot of privacy compared to a hotel. However, parking is much more convenient (and free!) compared to downtown hotels. We parked our car for 2 nights and had no issues. So, do consider those tradeoffs when you decide between an AirBnB in Boston vs. an inn/hotel!