I booked Sigma because I thought a private bath meant "ensuite" and not one that is outside of the room. The sheets felt dirty and smelly, not sure when they were last washed. The kitchen was full of clutter, and unclear what was okay to use for preparing a meal and what belonged to the folks who live there. On a positive note, instructions for checking in/out were super simple and clear. The price was good for such a great location near Harvard Square.