I had an excellent stay at Martha's cottage. It is a beautiful, private space which is perfect for a solo traveler - much better value for money than most 1-person rentals you could find in SF. The N-Judah line is about a 5-minute walk (down a hill from the house) if you are trying to get downtown.
My only worry looking at the pictures ahead of time was that (as a 6 foot 3 guy) the bed might be small, but rest assured, I could fit just fine!