Nora's listing is great. I don't believe that I have given 5 stars in each category before. The accommodations are quiet, safe and clean. While there isn't a kitchen there is a mini frig, microwave, coffee maker, dishes, glasses etc.
The on street parking with the visitor's pass provided couldn't have been easier.
The Somerville Community Path is a great bike / running path that is only a couple of blocks away.