My friend and I had a great stay at Kevin's place. It is exactly what we needed for our first time to Boston - the T could not be more convenient, and there's a great coffee shop (Brassica Kitchen) and pub/restaurant (Dogwood) just around the corner.
If you are a light sleeper, you may be awakened by the upstairs tenants. Otherwise, it is a great place with absolutely everything you could need (snacks, coffee, toiletries, comfy beds, etc) on a vacation. Kevin is quick to respond to questions, and has lots of helpful local tips. I definitely recommend his place to other guests!