I had stayed in one of their Beacon street apartments for a short term, less than a week. The daily rate was attractive, cheaper than a hotel stay in Boston. The place was ok, except for the flickering ceiling lights in the living room. The main problem I had was the lack of a refund policy with AAA Corporate Rentals. My friend, whom was staying with me, had pet allergies that were caused from the floor below us. Because there was a lease agreement, no refund was offered. Their management offered to relocate us to a different location. We decided not to.
If you're looking for a hotel alternative, there are better options for a short term stay in Boston without having to sign a lease.
To name one, I've had smoother time with firstchoicebnb.com which has comparable prices.